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two prominent
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  两个突出
     MW high temperature gas cooled reactor (HTR 10) has two prominent characteristics: (1) Gas turbine (GT) and steam turbine (ST) combined cycle, which can enhance power generation efficiency of HTR, as well, which can match low core inlet temperature.
     10MW高温气冷实验堆 (HTR 10 )有两个突出的特点 :(1)采用气体轮机和汽轮机联合循环 ,可以提高其发电效率 ,并且能保持较低的堆芯入口温度 (30 0℃ )。
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     There are two prominent problems existing in the studies of comprehensiveevaluation both at home and abroad now: the first one is the inconsistency amongthe evaluation conclusions drawn by different evaluation methods;
     目前国内外关于综合评价方法的研究,存在两个突出问题:第一,多方法评价结论的非一致性问题;
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     The paper possess two prominent characteristics: First, based on profound expatiating upon the theories of profit-model and using Management methodologies synthetically, a thorough and deep analysis about IKO's profit model has been contributed.
     本文具有两个突出的特点:第一,在对盈利模式深刻阐述的基础上,综合运用管理学的分析工具,对英考公司的盈利模式进行了详实的剖析。
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     Currently our country is faced with two prominent problems: on the one hand, with continuous and fast increase of national economy , our country gradually steps into new economy period characterized by economy globalization , knowledge economy and modern information technology ;
     当前,我国面临两个突出问题:一方面,伴随着国民经济的持续、高速增长,我国已逐渐跨入以经济全球化、知识经济和现代信息技术为主要特征的新经济时期;
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     How to decline the rate ofrecurrence and restore the anal function are always two prominent problems oftherapy for high fistula.
     如何有效降低复发率,保护肛门功能,一直是高位肛瘘治疗上存在的两个突出问题。
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  “two prominent”译为未确定词的双语例句
     The DTA curves have two prominent exothermic peaks between 720—830K.
     DTA曲线,在720—830K之间有两个明显的放热峯。
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     The dual-interface data access component based on OLE DB and data model supporting OGC are the two prominent characteristics of the paper.
     本文作者主要完成了系统的设计以及数据访问组件的设计和实现,其中基于OLE DB的双接口数据访问和支持OGC的开放数据模型是本文的两大特色。
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     The paper compares the performance of two prominent on-demand routing protocols for mobile ad hoc networks: Dynamic Source Routing(DSR) and Ad Hoc On-Demand Distance Vector Routing(AODV).
     重点比较Ad hoc网络中两种主要的按需路由协议:动态源路由(DSR)协议和Ad hoc按需距离矢量路由(AODV)协议。
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     Degradation of extra cellular matrix (ECM) and cellular migration are two prominent steps of tumor Metastasis.
     在肿瘤细胞的浸润和转移过程中,肿瘤细胞必须首先要通过ECM的降解,才能发生肿瘤细胞的浸润和迁移,并转移到他处。
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     19 sesame germplasm lines with more than two prominent trairs were identified. Their fat,protein,oleic and linoleic acids contents were over 56%,21%,42% and 37% respectively.
     筛选出具有两种以上优质性状的品种19个,其脂肪、蛋白质、油酸、亚油酸含量分别超过56%、21%、42%、37%。
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  相似匹配句对
     Two.
     二.
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     Two.
     二、末日意识
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     The contradictory between the two is extremely prominent .
     两者矛盾十分突出,城市土地集约利用成为我国城市化的必然选择。
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     In the period, antagonism is the prominent character in two countries' relations.
     这一时期,两国关系的显著特征就是尖锐对抗。
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     Prominent Scholars
     著名学者介绍
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  two prominent
This paper compares the performance of two prominent switching schemes of SM packet switches: Cell-Based Switching (CBS) and Packet-Based Switching (PBS).
      
The material which even today allows us to fill up these gaps is due to two prominent sixteenth-century legal humanists, viz.
      
The female head region set off from body, sometimes annulated, and the labial disc has two prominent elevations or bumps on the ventral side that are slightly raised above the medial lips.
      
In fact, two prominent features of immunosenescence are altered T cell phenotype and reduced T cell response.
      
To demonstrate the approach, the combination of two prominent approaches to damage detection is exploited: namely, the approach that utilizes the modal strain energy distributions and the one that utilizes the compliance distributions.
      
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On the basis of the measured ground data ten free air gravity maps of China have been constructed from mean free air values in square areas of 1°×1° to 10°×10° using average filter to eliminate successively the shorter wavelengths. These results indicate a great difference between East China and West China in the anomaly configuration: the anomaly value changes are gently in the East and sharply in the West: the short wavelength anomalies trend in a NE direction in the East and in NW in the West, whereas the...

On the basis of the measured ground data ten free air gravity maps of China have been constructed from mean free air values in square areas of 1°×1° to 10°×10° using average filter to eliminate successively the shorter wavelengths. These results indicate a great difference between East China and West China in the anomaly configuration: the anomaly value changes are gently in the East and sharply in the West: the short wavelength anomalies trend in a NE direction in the East and in NW in the West, whereas the long wavelength anomalies trend in a NS direction in the East and in EW in the West. In addition, there are four NW disturbance zones cutting across the NE linear anomalies in the East. From the map 1 (1°×1°) can be seen that in the East there exist two prominent nearly parallel positive anomaly zones, one of which extends from the Changbaishan mountains through the Liaoning and Shandong peninsulas into the coastal ranges in the Zhejiang and Fujian provinces, and the other runs from the Dahin-gganling mountains along the Taihangshan mountains through the Qinling mountains into the ranges of western Hubei and Hunan provinces. Between the two zones exist a wide and low gravity anomaly zone associated with the Songliao, North China and Jianghan plains and Hengyang basin. In the West, the anomaly configurations are very complex and have the same NW direction as the positive linear anomalies over the Qilianshan mountains, the eastern Tianshan and the Altayshan. On the map 2 (3°×3°) are shown the high-amplitude positive anomalies for almost all the mountain regions and the low-amplitude positive or negative anomalies for all the plains and plateaus, whereas the interior basins always correspond to the large high-amplitude negative anomalies. On the map 3 (5°×5°) can be found five dominant large anomalies for the China continent: the positive from 110°E to the east, the negative over the Sichuan basin and Ordos plateau, the positive over the Qinghai and Xizang region, the negative over the Neimon-ggol and Xinjiang Autonomous regions. Besides, a great negative anomaly appears in the eastern Xizang. As shown on the maps 4 and 5 (7°×7° and 9°× 9°), the direction of the main linear anomalies turns into a normal NS one in East China and EW in the West. It is suggested that the short wavelength anomalies (1°×1°) associated with the tectonic features are produced due to successive tectonic movements causing the non-homogenous mass distribution in the lithosphere. The moderate wavelength anomalies (3°×3° and 5°×5°) resulted from the broad bent of the lithosphere caused by the current stress from plate motions. Probably, the long-wavelength anomalies (7°×7° and 9°×9°) are related to the mantle deep-seated mass inhomogeneity, except the effect of the plate motions. The relation of the above-stated phenomena to the tectonic framework, isostasy, seismicity as well as the possible geodynamical process are also discussed.

本文利用地面实测的重力资料计算并构制了从1°×1°到10°×10°平均的中国大陆自由空气重力异常图,并对这套图中所反映出来的基本事实进行了分析和解释,且就这些基本事实与大地构造、地壳均衡、地震活动的关系及其可能的地球动力学过程进行了讨论。

We have studied the crystallization kinetics of amorphous Co_(78-x) Fe_x Si_8 B_(14) ribbons (x=5, 10, 20, 30, 40, at.%) by using the resistivity monitoring method in the higher temperature region and also with the method of differential thermal analysis (DTA). From 300K to 1000K, the ρ-T curves of the amorphous alloys with different x are all of the same shape with dρ/dT>0 before the crystallization starts and an abrupt drop △ρ of ρ during the crystallization process. The crystallization temperature T_(cr)...

We have studied the crystallization kinetics of amorphous Co_(78-x) Fe_x Si_8 B_(14) ribbons (x=5, 10, 20, 30, 40, at.%) by using the resistivity monitoring method in the higher temperature region and also with the method of differential thermal analysis (DTA). From 300K to 1000K, the ρ-T curves of the amorphous alloys with different x are all of the same shape with dρ/dT>0 before the crystallization starts and an abrupt drop △ρ of ρ during the crystallization process. The crystallization temperature T_(cr) lies between 750K and 830K and △ρ between 29 and 34 μΩ-cm. Experiments also show that after crystallization, the coercive force of these alloys increase conspicuously, some as high as 100—200 oersteds. The DTA curves have two prominent exothermic peaks between 720—830K. During the crystallization process, the curves display two distinct stages, showing that there are two crystallographic phases precipitated. In the vicinittt of the temperature of crystallization, we also measured the isothermal variation of resistivity with time of the ribbon Co_(58) Fe_(20) Si_8 B_(14). From the annealing curves and Arrhenius relation, the activation energy was estimated to be 80 Kcal/mole.

我们用测量在高温区电阻率随温度变化及差热分析(DTA)方法,研究了非晶簿带Co_(78-x)Fe_xSi_8B_(14)(x=5、10、20、30、40原子百分比)的晶化动力学。从300K到1000K非晶合金的电阻率(ρ)随温度(T)的变化曲线,在形式上是相似的,晶化前都有dρ/dT>0,在晶化期间电阻率的突变量Δρ也相近。晶化温度T_c,在750K到830K之间,而Δρ在29到34μΩ—cm之间。实验还表明,晶化后这些合金的矯顽力有相当大的增加,高到100—200奥斯特。DTA曲线,在720—830K之间有两个明显的放热峯。它所显示出的两个明显的阶段表明晶化时有两种晶相析出。在晶化温度附近,我们还测量了Co_(58)Fe_(20)Si_8B_(14)非晶簿带的电阻率随时间的等温变化。并根据退火曲线和Arrhenius关系,估算了其激活能为80千卡/摩尔。

Palaeomeryx was erected by Hermann von Meyer in 1834, who based his new genus chiefly on the presence of a "W?rst" on the posterior wall of the protoconid of DP_4 and the lower molars (later called the "Pnlaevmeryx-fold"), The fact that no associated antlers were found led von. Meyer to believe that Palaeomeryx might possibly be hornless. Subsequent discoveries of various kinds of "antlers" in association with teeth bearing the Palaeomeryx-fold made the genus Palaebmeryx conceptually ever-changing, and sometimes...

Palaeomeryx was erected by Hermann von Meyer in 1834, who based his new genus chiefly on the presence of a "W?rst" on the posterior wall of the protoconid of DP_4 and the lower molars (later called the "Pnlaevmeryx-fold"), The fact that no associated antlers were found led von. Meyer to believe that Palaeomeryx might possibly be hornless. Subsequent discoveries of various kinds of "antlers" in association with teeth bearing the Palaeomeryx-fold made the genus Palaebmeryx conceptually ever-changing, and sometimes very confusing. L. Ginsburg and E. Heintz's referral of two ossicones, allegedly pertaining to Palaeomeryx from Arteny , France, resurrected the dispute as to the content, affinity and taxonomic position of the genus Palaeomeryx. One of the main reasons for the controversy lies in the lack of complete skulls, to say nothing of skeletons. Till now there have been few records of the genus in China. E. Koken reported in 1885 several isolated teeth from Yummn (?) and erected a new species for them, Palaeomeryx oweni. Chen G. F. and Wu W. Y. (1976) and Li Y. Q. and Wu W. Y. (1978) mentioned some material of Palaeomeryx spp. from Cixian, Hebei, and Lantian, Shaanxi, respectively. All the above mentioned materials are too scanty to be helpful with regard to the paoblems concerned. The presence of Palaeomeryx fossils in Shanwang was first noticed by P. Teilhard de Chardin in 1939. There were two kinds of jaws, both with the Palaeomeryx-fold. The larger one, according to Teilhard de Chardin, "Would, without any hesitation, be determined as Palaeomeryx", "if they had been found in an European site". However, there was only one type of "antler", pertaining, judging by its size, only to the smaller form. As a result, he identified them as Palaeomeryx (?Lagomeryx) spp. A and B. The excavations carried out in the last years have luckily resulted in finding not only complete skulls, but also skeletous of Palaeomeryx. The significance of the discoveries is self-evident. Owing to the extremely fragile nature of the fossil bones and the technical problems in their preparation, we are tempted to publish the first observations on the most important aspects of the skulls and the skeletons before they can be available for detailed study. Description Pmaeomeryx tricornis sp. nov. Holotype V 7728, skull and associated lower jaw (much damaged daring preparation) with three cervical vertebrae. (Pl. III) Other Material 1. 820831~× complete skeleton, female (Pl. VI). 2. 830009~× complete skeleton, male (Pl. III) 3. 840002~× complete skeleton, male 4. 840015~× skeleton, female, the middle part of the vextebral column and the distal parts of the limbs are lacking 5. LV 8003~× incomplete skeleton, male 6. 820837~× part of skeleton 7. V 7729 skull, only the right side is exposed 8. V 7730 left P~2-M~3 9. V 7730.1 left P_4-M_3 Diagnosis of the species Size smmller than the medium-sized species of the genus. P_1 present (but not always), with or without a short diastema to P_2. Teeth brachyodent, corrugated. Metaconids on P_2-P_4 weakly individualized, forming no closod valleys on the inner side of the teeth. Palaeomeryx-fold well developed. Inner crests of P~2-P~4 barely divided by grooves on their inner walls. Upper malars propotionaly wider. Accessory comules of irregular form, but very well developed, labial to the posterior ridge of the protocone on upper molars. Cingulum and style (id) camparatirely weak. Male whith a pair of ossicones above the orbits and an occipital bony "horn" (may be characteristic for the genus in general). The ossicone is Very wide at its base, tapers rapidly and inclines backward. The occipital "horn" long, much dilated at its end. Description The only discernible sutures on the skull are those between premaxilla and maxilla, and between them and nasals. The nasals are flattened dorsally, and extend anteriorly to the level of the front of the upper canine, forming a small nasal notch over the premaxilla. The width at its anterior end is 18 mm, that at its posterior part is 24 mm. The premaxilla forms an oblique parallelogram, forming an angle of 45° with the alveolar border , but ilts anterior tip is rather pointed. The maxilla is rather high. At the posterior end of the nasal-maxilla suture a strip of matrix is exposed beneath the bones, evidently representing the ethmoidal vacuity (fenester ethmoidale). A large, oval (50×20 mm) and sharp-edged preorbital fossa is situated in front of the orbit. The fossa, extends beneath the lower border of the orbit. The infraorbital foromaen lies in front of P~2. The orbit is situated approximately in the middle of the skull (measured from basion to prosthion). The orbit is not outward protruded. The anterior edge of the orbit is damaged, but judging from the preserved parts it can be concluded that there is only one rather large lacrimal orifice on the inner wall of the orbit. Though the back part of the skull is more compressed, a forked sagittal crest is still traceable. The point of bifurcation lies at the level of the glenoid cavity. The delicate parts of the skull, the ear region and the basicranium are too crushed to provide useful informatians. Sexual dimorphism is clearly shown by the presenee or the absence of the "horn" structures. In the male, there a pair of ossicones and an occipital "horn". The ossicones are situated just above the orbits. The surface of the ossicones is rough and cancellous. On the type skull a rough suture can be observed, which separates the ossicone from the skull. Since the skull belongs to a rather old individual. judging by the strongly worn teeth, it must mean that the ossicone was unankylosed to the skull roof until late in life . Unfortunately we could nat find a similar suture in the other male skulls at our disposal. Probably the ankylosis may occur irregularly, earlier or later in life. Seen from the lateral side, the ossicone is triangular in form, slanting strongly backward. Its anterior margin is far beyond the anterior border of the orbit, while its posterior margin which is concave anteriorly. lies approximately at the level of the posterior border of the orbit. The ossicone is strongly compressed laterally. In the type skull the tip of the ossicone is a little swollen, in other skulls the tips may be pointed. So the ossicone varies in form. The occipital "horn" is morphologically. and histologically different from the ossicones. The surface of the "horn" is smooth, like the surface of any ordinary bone. The lambdoid crest extends upward to the middle of the "horn". The uppermost part of the "horn" is ornamented with fine knots and striations, but this is the usual roughening of the bone surface, as in the case of the "horn" of brontotheres. Seen from the side, the "horn" resembles a large bulb sitting on a stout pedicle. Laterally it is compressed, and seemingly unforkcd, unlike that in Triceromeryx. The upper canine in male is large and sabre-like, with a stout root. The most robust part of the tooth is in the middle of the root (20×10 mm). The demarcation between the root and the crown of the tooth is vague. The anterior margin. is rounded, while the posterior is trenchant. The crown is rather flat externally, but convex internelly (opposite to Teilhard de Chardin's description). Seen from the antero-posterior direction, the tooth is bent, with its tip turned externally. The upper canine of a female individual is very small and peg-like. There is no P~1, the diastema between canine and P~2 on the type skull is about 40 mm. The P~2 is provided with a very strong paracone rib on the labial wall and deep groove in front of it. There is no clear central groove on the lingual wall of the tooth on the type specimen, while on other specimens the groove is very weakly developed. P~3 resembles P~2, with the inner crest more robust, making the tooth more triangular in form. P~4 is markedly shorter than its preceding teeth, but wider. There are two prominent swellings on the labial wall: the parastyle and the paracone rib. Seen from the labial side, the former takes a form of low triangle, while the latter is long and ridgelike. They converge at the base of the crown. The paxacone rib overlaps the groove which lies in front of it. The posterior wing of the protocone is composed of two ridges. The labial one is higher than the lingual one, but the valley between them is very shallow, so that slight wear will change the two ridges into one brad wear surfaec. A weak cingulum runs along the anterior, lingual and posterior sides of the tooth. The three molars are alike in structure. Parastyle and paracone ribs resemble those in P~4. The mesostyle resembles the parastyle in form, but more robust, forming the most labial point of the tooth. The metacone has a mope oblique orientation than the paracone, and has a fine rib on its outer wall. The posterior wing of the protocone is directed more posteriorly than postero-labially, furthermore, it Points to the middle of the anterior wing of the metaconle, rather than to its labial end. Labial to the posterior wing of the protocone there is a conule of irregular form. The form of the conule changes from M~1 to M~3. For the M~1 it takes the form of a knob with two short arms, one of which points lingually, the other posteriorly to the anterior wing of the metaconule. In M~2 this conule has the form of an upside-down "L", while in the M~3 it changes into an upside-down "Y". In later deer the posterior wing of the protocone is construtted differeatly , consisting of two well formed ridges; the labial one stronger than the lingual one. E. Heintz called the labial ridge the Protocone ridge proper, and the lingual one protocone-fold. It is opposite to what we observed in Palaeomeryx. The anterior wing of the metaconule does not reach the inner side of the mesostyle. The me~eonule has a fine rib on its labial wall. Its posterior wing divdes into two thin ridges at its posterior end. One stretches toward the metastyle, while the other, and smaller one, points to the base of the inner wall of the metacone. The cingulum is developed on the anterior and posterior sides. An entostyle is variably developed, but in general it is rather weak. No complete lower incisors and canines are preserved. What left are only their reots. They are rod-like, and stand in a row tightly one after the other. There is no diastema between I_3 and the lower canine. Judging from the small part of the preserved crown, the lower canine seems to be single-cusped, not double-lobed, as in giruffids. P_1 is present at least on three of these specimens. It is small, laterally compressed and single-cusped. A small diastema occus between it and P_2, not longer than 10 mm. In one specimen, LV 8003, P_1 stands close to P_2. On the type specimen only the posterior half of P_2 is stitl preserved, while in another specimen, LV 8003, only the outer wall cad be seen. The protoconid, which is centrally situated, sends a low crest posteroligally. There is no metaconid, and the entoconulid-crest is not fully developod. The P_3 has three fully develaped transverse crests. The crest, which connects the protoconid and metaconid, is diagonally oriented. The metaconid is poorly individualized from the crest, and is situated behind the protoconid. The poserior two crests are not strictly parallel: the entoconulid forms a curve, and approximates the entoconid at both its extremities. The valley between the two crests is shallow. P_4 resembles P_3 in structure, but it is larger. Its posterior two crests are parallel. The protoconid forms an independent crest, and there is a clear groove on the labial wall, just opposite the entoconid. An internal cingulum is present only before the metaconid, which is much better individualized. The molars. except the third lobe of M_3, are structurally alike. The protoconid first connects with the metaconid, then through a tiny enamel tubercle with the posterior end of the paraeonid. Palaeomeryx-fold is alway very well developed. The connegrons between the anterior ends of proto-and Paraconid, and between the posterior ends of hypo- and metaconid are both very low, leaving gaps on the outer wall of the tooth. The former can not be seen owing to the overlepping by the preceding tooth, but the latter can be clearly. seen from the side. The mesostylid is strong, and forms the most lingual point of the tooth. A weak cingulum is preseut on the anterior and posterior sides. The ectestylid is always present between the two lobes. The third 1obe of M_3 takes the form of a horse-shoe, the inner arm of which is 1ow and conneets with the posterior end of the metaconid, while the labial arm goes to the middle of the posteriot wall of the hypoconid. No indication of the special prolongation of the neck is observed. The length of the seven associated cervical vertebrae is only about as long as the basial length of the skull. All the neural spines of cervioal vertebrae II-VII are well developed and platelike, among which that of the axis is especially broad (antero-posteriorly), with the top strongly overhanging anteriorly. The thoracic vertebrae are 13 in number, lumbar vertebrae probably 6, the neural spines of which are broader then those of the cervical ones. The munber of the caudal vertebrae is unknown, but it must be very short, probably extends not much beyond the posterior end of the pelvis. The humerus is shorter than scapula. The intermediate ridge on the distal articular surface of the humerus, seen from the front, stretches not vertically, but with its upper extremity turned laterally. The shaft of the ulna is thin, but fully preserved. Among the carpal bones there are only scaphoideum, magnum, triquetrum and pisiform, which are detached. Morpihlogically they ate quite deer-like. McIII and IV ate completely fused, with the central groove on the front face of the bone distally closed. McII and V are slender, but preserve their full length, and each with a complete set of phalanges. The proximal part of the two lateral metacavpals has shifted to the posterior side of MeIII-IV, The hind limb is longer than the fore limb in general. The tibia longer than the femur. The metatarsals are similarly constructed to the metacarpsals. The central groove on the frontal face of the canon bone is distally closed as well. Diseussion For more than half a century after the erection of the genus most of the German language speaking paleontologists adhered von Meyer's original concept of the genus, that is, they lumped all species having the teeth with a Palaeomeryx-fold into the genus Palaeomeryx, regardless of the marked, sometimes even radical, differences in the "antlers" of these species. However, gradually a series of genera have been extracted from the overly lmnped aggregation. These genera are, for example, Amphitragulus Pomel , 1846, Dicrocerus and Micromeryx Lartet, 1851, Procervulus Gaudary, 1878, Prox Hensel, 1859 (=Euprox Stehlin, 1928), Lagvmeryx Roger, 1904 and Heteroprox Stehtin, 1928, among others, A historical review of the vicissitudes of these genera is given in the text in Chinese. We adopted the conception of the genus proposed by L. Ginsburg and E. Heintz in 1966, with the only emendation that both Asia and Africa may well have their local representatives of the genus. According to the two French paleontologists, there are only three species: P. kaupi (=P. bojani, =P. garsonini), P. magnus (=P. sansaniensis) and P. eminens (=P. nicoleti). Since the Shanwang material provided for the first time so much reliable informations for the genus, it is desirable to give a revised diagnosis for the genus: A primitive group of giraffoids. Size comparable with medium to large deer. Skull dolichoeephalic, orbit central in position. Angle between the basicranial and the palatal surfaces almost 180°. Both preorbital fossa and ethmoidal vacuity present, one lacrimal oriface within the orbit. P_1 present in primitive species. Teeth brachyodont, strongly corrugated, with well developed cingulum and style (stylid) and paracone rib. Molarization of premolars low, transverse valleys seldom closed lingually. Posterior arm of protocone directed posteriorly, a prominent conule situated labially to it. Prominent Palaeomeryx-fold. Neck and limbs not specially elongated. Hind limb longer than foreleg. Canon bone with distally closed groove on dorsal face, its distal condyle with strong keel. Lateval metapodia (II & V) slender, but preserved full length, with full set of phalanges. Sexual dimorphism. A pair of orbital ossicones and an occipital bony "horn" as well as sabre-like upper canine in males. The affinity, hence the systematic position of Palaeomeryx, as stated above, has been the subject of controyersy. There are two main contradietory points of view, represented by L. Ginsburg and J. Leinders respectively. The former insists that Palaeomeryx should be included in Giraffoidea, while the latter argues that Palaeomeryx is a member of Cervoidea, and Giraffidae must be placed with the Bovidae. The reader, who is interested to know these poimts of view in detail, is referred to the papers written bv L. Ginsburg and E. Heintz (1966) and by J. Leinders (1984). The discovery of the Palaeoqneryx skeletons in Shanwang contributes the following information to this problem: 1. The discovery has proved the eorreetness of Ginsburg and Heintz's attribution of a pair of ossicones to Palaeomeryx. The Shanwang material shows clearly that Palaeomeryx has ossicones of definitely giraffid type. The form. structure, position and the relationship of ossicones to the skull bones are all uniquely conformable with the ossicones of giraffids. What is more, an occipital bevy "horn" has been found so far only in two ruminants forms: Triceromeryx and Cranioceras (Procranioceras). As to the affinity of Triceromeryx, the opinion is still controversial. However, its giraffid type of P_4 (Crusafont-Pairo, 1952, Pl. XIII) supperts its inclusion in lineage of giraffids. Unfortunately, the true nature of the American genus Cranioceras and its like is still not clear. The presence of giraffid ossicones in Palaeomeryx is Ginsburg's main argumentation for his inclusion of Palaeomeryx in Giraffoidea. In this respect our new discovery substantiates strongly his point of View. The extreme rarity of the occuvrence of ossicones. in the fossil record lies, at least partly, in the phenomen of sexual dimorphism. 2. The doliehocephaly, the central position of the orbit and the gentle bend of the cranimn relative to the facial portion, which we observed in Palaeomeryx trivornis, may constitute a complex of correlated features, characteristic of the giraffids. In general the last two features are considered plesiomorphic for the Ruminantia. However, they are never combined with so long a skull as in Palaeomeryx. Therefore, the combination of the three features is probably to be considered as apomorphic for giraffids. Similar comIbination of features can be found, for example, in Zarafa (Hamilton, 1973, Pl. 2) and Giraffokeryx (Colbert, 1933, fig. 1), both genuine giraffids. 3. Contrary to Ginsburg and Heintz's assertion, Palaeomeryx does have an ethmoidal vacuity. Ginsburg and Heintz were not correct either, when they stated that gimffids are lacking this vacuity. In fact, not only in recent forms, Okapi, and sometmes Giraffa (for example, in one of the skulls in our instipule), but also in fossil forms, Zarafa (Hamilton, 1973, p. 87), Giraffokeryx (Colbert, 1933, p. 7) and Palaeotragus (Bohlin, 1926, p. 11) may possess this vacuity as well. However, it is evidently a plesiomorphic character within the Pecora. It plays thus no role in deciding whether Palaeomeryx belongs to Giraffidae, or Cervidae or even Bovidae. 4. Palaeomeryx has one lacrimal orifice within the orbit. In this respect it is similar to Bovidae. However, from what we leadned from the evolutionary trends in Cervoidea it can be safely deduced that the direction of trensformation of this feature is from one orifice within the orbit to two orifices on the orbit margin. It is well known that the primitive Cervoidea always possess one orifice in the orbit, as in mereboys of the Tragulidae, and even Moschus, but the true deer have only the second type of lacrimal orifices. So, again, the character is plesiomorphic. 5. Palaeomeryx possesses a preorbital fossa and a sabre-like upper canine in males. The former is one of the characteristic features of the Cervoidea, while the latter is very common among the members of the group. Neither have been found in the Giraffidae, or Bovidae. The polarities of these two characters are unknown to us. Since Cervidae, taken as a whole, is considered as an archaic group in Pecora, the above mentioned characters may well be retentions of plesiomorphic features. 6. The cheek teeth of Palaeomeryx, as indicated by Hanilton (1973, p. 94), are very similar to those of Zarafa. In fact, in morphology of the cheek teeth, Zarafa links Palaeomeryx with the later forms of Giraffidae so well, that Hamilton, after having described his Zarafa material, was convinced of the giraffid affinity of the genus Palacomeryx. However, later, based on the belief that these similarities in the cheek teeth were only of plesiomorphic features, he favoured the opinion that Palaeomeryx could be classified with Bovaidea (Hamilton, 1978). It seems to us that the similarities in the cheek teeth between Palaeomeryx and Zarafa are much more than those between Palaeomeryx and Triveromeryx, although many paleontologists were strongly impressed by the similarties between the latter two forms, when Triceromeryx was first described. We are inclined to believe that the common features of Palaeomeryx and Zarafa are not totally plesiomorphic. Some of them could be synapomorphies, for example, the extremely dveloped style (styfid) and ribs, and the prominent accessary conules labial to the posterior wing of protocone on the molars. They have never been so strongly developed in Cervidae, to say nothing of Bovidae. 7. The central groove on the dorsal face of canon bone is here distally closed, as in all advanced forms of deer. This is the main, and in fact the sole criterion, on which J. Leinders moved Palaeomeryx into the Cervidae. Leinders has never unequivocally deciphered the polarity of the character concerned. From the context one can see that he seems to consider the closed-groove as a derived character relative to the open one. The question rises: why he based his Bovoidea (=Giraffidae+Bovidae) on a plesiomorphic character (open-grvove)? This led us to inquire in more detail into the problem retating to the potarity of the canon bones. The results are: (a) The polarity is from open-groove type to closed-groove one. This polarity is clearly demonstrated by the presence of open-groove type in the most primitive forms of deer, like Gelocus Kowalewsky, (1876-77, Tab. II, 19) and Leptomeryx (Matthew, 1908, fig. 9). Thus Leinders' Bovoidea (=Bovidae+Givaffidae) is based on plesiomorphic character (open-groore) and hence questionable. b) Although the closed-groove type is a derived character, it could be independently derived, through parallel evolution in different phyla within the Ruminantia. The Antilocapridae provide a good example in this respect. While the recent pronghorn has a closed-groove type canon bone, some primitive fossil forms may have an open-groove type, for example, the canon bones of Merycodus cf. furcatus (=Cosoryx (Paraeosoryx) furlongi, Frick, 1937) are of open-groove type (Furlong, 1927, fig. 16). The identigfication of Furlong's material as belonging to a primitive form of Antilocapridae is irrefutable, because the skull, which was associated with the above mentioned foot bones, is evidently of antilocaprid affinicy. The inevitable conelusion to be drawn from the feregoing statments is that, when Antilocapridae branehed off from the general stem of Pecora, it must still have an open-groove canon bone, and then at some later time changed into the closed-groove type characteristic of the living pronghorn. 8. Our observations on postcranial skeletons reveal no principal differenees between Palaeomeryx and the typical Cervidae. Some of the differeilces listed by Ginsburg and Heintz as characters shared with giraffids are untanable. Contrary to the statment of Giusburg and Heintz, the hind limb of Palaeomeryx tricornis is evidently longer than its forelimb. However, this should not present an obstacle to the linkage of Palaeomeryx with Giraffoidea, as the true giraffid, Zarafa, has no less deer-like postcranial bones than Palaeomeryx. As a result, the available evidence is in favour of Ginsburg's point of view that Palaeomeryx may share more derived characters with giraffids than with cervids, to say nothing of bovids. At the same time it should be noted that Palaeomeryx must be very primitive, with many plesiomorphic characters shared with cervids. In this case the closed-groove type of the canon bones must be considered as the result of parallel evolution. One of the eonsequences of the present hypothesis is the separation of giraffids from Leinder's Bovoidea. Judging from the evolutionary level of Palaeameryx, it is to be inferred that the giraffids, Palaeomeryx included, originated after Gelocus and Leptomeryx, and before Blastomeryx and Eupecora in the sense of Webb and Taylor (1980). In comparison with the European species, Palaeomeryx tricornis is comparable only with the small species, P. kaupi. The other two species. P. magnus and P. eminens, are much larger and more advanced than ours. The molarimtion of the premolars, espectally P_4, in the two larger species is evidently higher than in ours. Unfortunately, P. kaupi has not been properly studied. At any rate the distinetdon between the Shanwaug species and the European ones is clear. In none of the European species there exists a P_1, primitive character of Palaeomeryx tricarnis. Furthermore, the cingulum is generally weak in our form, while it is markedly developed in European species. It seens that the upper molars of the Shanwang specimens are proportionally wider. Probably there are also some differences in the form and size of the ossieones or "horns" between them. The only record of the ossicones, from Artenay (Ginsburg and Heintz, 1966), belongs most probably, to P. kaupi, because at that locality the only recorded species is P. kaupi. The above mentiongd ossicones are proportionally slender at their bases. No occiipital "horn" has been so far reported from Europe. These differenees, it seems to us, warrant the separation of the new material as a new speies: Palaeomeryx tricornis. ap. nov. According to Ginsburg and Heintz, the European Palaeomeryx icereased regularly in size, and this may serve as good indicator of geological age. In size our specimens are comparable to those from Pontlevoy (MN 5) and Baigneaux (MN 4b). Strictly speaking, our specimens are among the smaller of Pontlevoy matorial, but a little larget than those from Baigneaux. In case the Chinese form represents a sepurate lineage, diffferent from its European relatives phylogenetically, its age may be older or younger. Acknowledgments Special thanks are here extended to Dr. L. Ginsburg, Mus. nat. d'Hist. nat., Paxis and J. Leinders, Institute for Earth Sciences, Utrecht, far their great help in sending casts, unpublished manuscripts

Palaeomeryx 在含义、性质和分类位置上,一直是一个争论较多的属.最近在山旺发现的 Palaeomeryx 完整骨架,为解决上述问题提供了有价值的资料和证据. Palaeomeryx 雄性具有一对眶上"皮骨角"和单一的"枕顶角".根据共近裔性状的分析,本文作者认为 Palaeomeryx 应该归入长颈鹿,作为这一支中最早分出的一个旁支.长颈鹿和鹿科有较近的亲缘关系,而和牛科的关系较远. Palaeomeryx 大概位于 Blastomeryx 和 Leptomeryx 之间,从反刍类主干中分出.山旺的材料,代表本属中一个较原始的新种: Palaeomeryx tricornis. 它的时代,可能相当于欧洲的 MN4 或 MN5.

 
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