230 



THE GEOLOGIST. 



ments, we see tliat tlie young oran-outan, gorilla, and chimpanzee 

 have the transverse diameter of the skull proportionately equal,* and 

 that the apparent length of the head in the chimpanzee is produced 

 by the greater development of the supraciliary ridges than in the 

 oran-outan. In the young gorilla, also an African ape, coincident in 

 its geographical distribution with races of dolichocephalic negros, 

 the transverse diameter actually slightly exceeds in Deslongchamps' 

 5th plate that of the oran-outan. For all practical purposes of 

 classification, however, it may be said that in youth, before the action 

 of the biting muscles has altered the typical outward aspect of the 

 brain- case, the oran-outan, gorilla, and chimpanzee exhibit skulls of 

 which it cannot be predicted that each exceeds the others in the pro- 

 portion of its transverse diameter. 



Professor Deslongchamps says, " Pour bien saisir les rapports, 

 souvent caches, des etres entr'eux, I'etat adulte ne suffit pas toujours ; 

 dans cet etat, ce sont surtout les differences qui se prononcent ; dans 

 les premiers ages, les ressemblances sont plus accusees, les affinites 

 sont moins masquees. 11 est utile, dans I'etude des animaux, d'imiter 

 les botanistes, qui vont chercher les affinites des genres et des families 

 des vegetaux dans les premiers rudiments des fruits, de la graine, de 

 I'embryon, etc. Le groupe des singes anthropoides est remarquable 

 entre tous par les changements, je dirais presque par les metamor- 

 phoses, que subissent leurs tetes."t The comparison of the skulls of 

 the anthropoid simise in their young state, made by the cautious and 

 philosophical Dean of the Faculty of Sciences at Caen, therefore, 

 may be accepted as evidence against the hypothesis of the coincidence 

 and derivation of the short and long-headed races of men with and 

 from the alleged brachy- and dolichocephalic genera of Asiatic and 

 African apes. 



The foregoing table is drawn up with a view to exhibit generally 

 the num.ber and proportions of extinct and existing mammalia which 

 have been found in a fossil state in deposits where the remains of 

 man have also been discovered. With no pretensions to complete- 

 ness, it may yet serve as a convenient record, and may, to a certain 

 extent, demonstrate the greater antiquity of e. g. the Abbeville beds 

 as compared with the Danish Kjokkenmoddings, evinced by the 

 greater proportion of extinct species in the former deposit. It must 

 however be borne in mind that the mammalia of the Somme valley 

 may not have attained a more northern range during the post- 

 pliocene age, whilst boreal species existing in England and Denmark 

 at the same time might leave no remains in post-pliocene strata in 

 Gascony or Sicily. We know too little respecting the distribution 

 of maiumalia over limited areas in the later tertiary strata to entitle 

 us to form any comprehensive generalization. 



In this table, 1 have made use of the researches of M. Lartet 

 (Geol. Journal, 1860, p. 471 and 491, and Natural History Eeview, 

 18G2, p. 53); Mr. Prestwich (Geol. Journal, 1860, p. "189, and 



* Sur lo Gorilla, par Profcsscur Owcu, avec six planches ajoutees par Eudes Desloug- 

 chniups. 8yo. Cam. 18G1. 

 t Loc. cit. p. G. 



