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and phylogeny of the family to base any far reaching conclusions on them. Excluding the little known forms Propalæomeryx (= Progiraffa) and Giraffa (?) priscilla, Giraffokeryx is the only Giraffoid definitely known from the Chinji stage. Giraffokeryx may be quite properly regarded as a Palaeotragine allied to the Pontian species P. quadricornis. Its horns and other characters however, clearly indicate that it belongs to a different genus from Palæotragus. I am still almost convinced that it represents an early specialization ancestral to the Sivatherines and from Bohlin's and Colbert's remarks it may be inferred that they are inclined to hold the same opinion. In any case it is agreed that the Palæotraginæ are the most primitive of the various sub-families of the Giraffidæ. On the assumption that the Chinji is Pontian, the typical large Sivatherines which occur at Pikermi as Helladotherium might we imagine have accompanied Hipparion to India, as also the more characteristic large Palæotragines such as Samotherium of Samos and China, and Alcicephalus of Maragha and Central Asia, as also the Giraffina, Orasius or Giraffa. I cannot, therefore, see how the Chinji Giraffoids add any evidence for correlating the Chinji with Pikermi or the Hipparion fauna of China.
The Chinji Suidae include species of Listriodon, Conohyus and Palaeochoerus which are almost too close to Vindobonian species of Europe to be called relicts instead of migrants. Their almost identical features to the European species is truly remarkable. It would be still more surprising if they persisted into the Pontian of India according to Colbert's theory. It may be remarked that Listriodon persists into the Pontian of Europe, but it equally is found in the Dhok Pathan. There also exist in the Chinji what may be endemic groups of Suidæ, to which the names of Propotamochoerus and Dicoryphochoerus have been given. They resemble nothing which has been found in the Pontian of Europe. On the other hand the type of Microstonyx which extends from Europe to China did not penetrate to India.
It is true that Hyænidae allied to Crocuta eximia and Lycyaena chaeretis occur in the Chinji stage, but Crocuta carnifex is clearly more primitive than C. eximia and C. variabilis. Hyænidae at the same stage of evolution as the two last named species, wide spread as it was in Europe and Central Asia, did not reach India before the Dhok Pathan. Lycyaena parva and L. chinjiensis are very much smaller species than the large L. chaeretis and may be ances
tral to it. The larger type of Pikermi is unknown in India before the Dhok Pathan, where L. macrostoma is closely allied to it.
It is the same story with every group of mammals whose remains in India are well enough known to enable a judgment to be formed. The Pontian Sivaonyx and Enhydriodon did not migrate to India in the Chinji stage, although a form which may be ancestral to both of them, Vishnuonyx, existed at Chinji. The large Macharodonts and Hemicyoninæ which are a feature of the Pontian of Europe and China fail to appear in the Chinji any more than the primitive buffalo, Parabos (?) macedoniae, or Orycteropus, though the latter has been found in the Nagri stage.
I may again revert to the argument which has already been brought forward elsewhere (Pilgrim, 1931, p. 151) and has been in part alluded to in the preceding pages. Matthew and Colbert suppose that the Chinji is of Pontian age and that its fauna largely arrived in India at a time when a very different fauna inhabited Europe itself. In spite of this it seems very remarkable, to say the least, that so many forms should exist in the Chinji which are more primitive than, if not actually ancestral to forms in the Pontian of Europe and the Dhok Pathan stage of India alike. Many of these lineages are actually unknown in Europe before the Pontian, so that even if they migrated from India to Europe, they could not have done so in the Dhok Pathan, since according to Colbert's hypothesis the Dhok Pathan is post-Pontian. To name a few of such forms. Sivaceros is an ancestral type of Tragocerus; Sivoreas of Prostrepsiceros; Strepsiportax of "Tragocerus latifrons; Vishnuonyx of Sivaonyx and perhaps of Enhydriodon; Crocuta carnifex of Crocuta eximia, C. variabilis, C. gigantea and C. mordax; Propontosmilus sivalensis of Epimachairodus; Lycyæna proava and L. chinjiensis of L. macrostoma and L. chaeretis. Finally the Chinji stage contains species of Proboscidea which are ancestral 1. to Mastodon (Choerolophodon) pentelici and M. (Choerolophodon) corrugatus and 2. to Mastodon longirostris and M. perimensis (see Hopwood, Appendix pp. 72-75).
This brief review of the Chinji fauna entitles us to ask for a reasonable explanation of the fact that Hipparion alone of the rich Pontian fauna was able to reach India contemporaneously with its appearance in Central Asia and Europe.
It might be contended that the Chinji fauna, though pre-Pontian, is not contemporaneous with the Tortonian fauna of La Grive Saint
Alban, but as Lewis thinks, with that of the Upper Sarmatian of Sebastopol or even with that of the Sarmatian of the Vienna basin, which contains a few Tortonian species such as Conohyus simorrensis, Anchitherium aurelianense, Amphicyon major, Ursavus, Aceratherium tetradactylum and Ceratorhinus sansaniensis, and which probably belongs to the lower part of the Sarmatian. It is true that such a correlation either with the Upper or Lower Sarmatian would harmonize with the peculiar character of the Chinji fauna as ancestral both to the Dhok Pathan and the Pontian of Europe and China. On the other hand, the intermediate position of the Nagri fauna between those of Chinji and Dhok Pathan affords the best argument against this view.
The sharp lithological change from the bright red clays of the Chinji into pale green sandstones of the Nagri does not necessarily indicate any great interval of time between the two stages, so that certain species which have been found near the base of the Nagri may not be much later than those of the Chinji. At the same time since the fauna of Nagri itself, of Haritalyangar, of Bahitta and certain other localities in the neighbourhood of Hasnot lies some 1500 to 2000 feet above the base, these afford good evidence for the intermediate character which I have mentioned above.
The following may serve as instances of this. Gaindatherium browni from the Nagri stage, one mile south of Nathot, is also found in the Chinji, but is absent from the Dhok Pathan. Macrotherium passes up from the Chinji into the Nagri, but is absent from the Dhok Pathan. The typical Chinji Anthracotheroid, Hemimeryx pusillus is also present at Nagri, but is replaced in the Dhok Pathan by Merycopotamus. Conohyus indicus is a a true survival of the Chinji C. chinjiensis but of much larger size. The genus does not persist into the Dhok Pathan but is replaced by Tetraconodon. Equally Propotamochoerus and Dicoryphochoerus are represented by identical or closely allied species in the Chinji and Nagri. The gigantic Dhok Pathan species Dicoryphochoerus titan has not, however, yet appeared in the Nagri. On the other hand the occurrence of a true Sus and of Hippohyus in the Nagri distinguishes it from the Chinji. Dorcabune nagrii is probably closer to the Dhok Pathan D. latidens than to the Chinji D. anthracotheroides. The Giraffida afford good distinctions between the three stages. Giraffokeryx punjabiensis, common in the Chinji, passes up into the Nagri,
but does not persist into the Dhok Pathan. A Giraffid intermediate in size between Hydaspitherium megacephalum and Giraffokeryx punjabiensis has been provisionally referred by Matthew (1929, p. 545) to Vishnutherium sp. indet. The large Sivatherines like Hydaspitherium and Bramatherium, which are typical of the Dhok Pathan do not, however, occur in the Nagri. It is likely that certain typical Chinji Boselaphinæ such as Strepsiportax and Helicoportax just enter the Nagri, but soon die out. The basal beds of the Nagri yielded the type skull of Selenoportax vexillarius. This species appears to be absent from the Chinji but is plentiful in the Dhok Pathan. Pachyportax nagrii, supposed to be ancestral to the Dhok Pathan P. latidens, is absent both from the Chinji as well as the Dhok Pathan. The genus Sivaceros is represented both in the Chinji as well as in the Dhok Pathan, but certain large species of it appear to be confined to the Nagri. Tragoreas (?) potwaricus represents a more primitive stage of development than either T. oryxoides of the Pontian of Europe or T. (?) lagrelii of the Pontian of China. So far it has only been found near the village of Nagri. The absence from the Nagri of the common Dhok Pathan genera Tragocerus and Tragoportax which are typically Pontian seems to be very significant.
Amongst the Carnivora Amphicyon, a typical Chinji genus, is also found in the Nagri but does not persist into the Dhok Pathan, Sivanasua does not persist into the Dhok Pathan, but is represented. in the Nagri by a species S. himalayensis, which differs from the Chinji S. palacindicus. Vinayakia occurs both in the Chinji and the Nagri but the Nagri species, V. nocturna is decidedly more advanced than the Chinji V. sarcophaga. The genus does not persist into the Dhok Pathan but seems to be replaced by Mellivorodon. Crocuta carnifex, the earliest representative of the Hyænid lineage which has a reduced protocone in p1 is confined to the Chinji but a more advanced species C. gigantea var. latro is found both in the Nagri and the Dhok Pathan. C. mordax, close to the Pontian C. eximia and C. variabilis has only been found in the Dhok Pathan. Megantereon has not been found in the Chinji but the species M. praecox from the Nagri (or Dhok Pathan) stage of Haritalyangar is probably ancestral to forms which occur at later horizons. Considering the comparative poverty of the Carnivorous fauna of the Nagri stage no stress can be laid on the absence from it of numerous typical Dhok Pathan genera.
Since the Nagri fauna seems to fulfil precisely the requirements which would render it the equivalent of the Sarmatian of Europe, it does not seem probable that the older fauna of Chinji can be referred to the same age as any of the known Sarmatian faunas of that continent.
An unpublished remark of Dr. Hopwood has suggested to me one other possibility. This is that the Chinji fauna, though later in age than that. of La Grive Saint Alban is earlier than any of the known Sarmatian faunas. It is quite conceivable that the mammalian faunas of the Upper Miocene of Europe do not represent a continuous chronological sequence and that none of the European deposits have so far yielded a fauna which is strictly contemporaneous with that of Chinji. Such a fauna might tend to bridge the remarkably abrupt gap between those of La Grive Saint Alban and the Sarmatian. Whether it should be termed Upper Tortonian or Lower Sarmatian is a matter of taste. The hypothesis is at present insusceptible of proof and in any case even if substantiated would hardly account for the pre-Sarmatian migration of Hipparion from North America into Asia. It serves, however, to emphasize the fact that I do not regard the correlation of the Chinji stage as so precise as that of the Dhok Pathan. In calling it Tortonian I have accepted it as the approximate equivalent of that of La Grive Saint Alban, merely because no other known fauna of Europe seems to fill the place.
From the comparisons made above (pages 446-464) between the Tatrot and Pinjor faunas and those of the Astian, Villafranchian and Cromerian of Europe, it is evident that no greater influx of the contemporaneous European and Chinese faunas of the Villafranchian and the Cromerian into India can be noticed than has been seen to be the case in Pontian and Astian times, using Matthew's and Colbert's chronology. In other words. on their hypothesis migration into India has been successively retarded stage by stage. throughout the long period extending from the Vindobonian to the Cromerian. Such a phenomenon is within all experience unparalleled and is to my mind incredible. The incredibility of the nature and chronology of the processes involved by our acceptance of Matthew's and Colbert's theory would be at once placed into the region of impossibility if we could show that India was the adaptive centre of any of the groups which have been assumed to migrate in this bizarre fashion. Although it would be rash to assert