AND AFFINITIES OF TARSIUS, 493 



"witli a posterior wall in the foraiation of ^Yllicll the alisplienoicl 

 takes part. (xiTi.) The liyoid, with its I'elatively short '-lesser" 

 coriiua, (lifters from the typical hyoid as seen in the Lemiu-s, and 

 resembles that of the monkeys and apes (Burmeister's ftgure 

 and account of the hyoid does not accord with the condition 

 present in my specimen), (xiv.) The trachea is not formed upon 

 the peculiar lemurine fashion, for the rings are incomplete behind, 

 as they are in the Anthropoidea. (xv.) The two halves of the 

 mandible ar.e synostosed in the middle line, (xvi.) The ventral 

 pelvic symphysis is shallow, a,nd is limited to the pubis. In the 

 gastro-intestinal tract the very widest differences exist between 

 Tarskis and any members of the Lemuroidea, and for the 

 purpose of summary we will only note (xvii.) the simplicity of 

 the gut pattern of Tarsius, and the absence of any coiling which 

 is so characteristic of the Lemurs. In many features the 

 myology of Tarsius dift'ei'S from that of the Lemurs a,nd resembles 

 that of the Monkeys and Apes ; as an example, (xviii.) the very 

 human disposition of the digastric muscle may be instanced. In 

 the vascular system (xix.) the ai'rangement of the vessels on the 

 arch of the aorta provides a striking contrast to the condition 

 seen in the Lemurs. 



In summing up the entire anatomy of the Lemurs and of the 

 Monkeys and Apes it is impossible to avoid appreciating '-the 

 differences in structure that indicate the wide separation of 

 the Lemuroidea and the Anthropoidea" (Elliot Smith, ' Nature,' 

 May 2, 1907, p. 7). Judged by such standards as are commonly 

 employed in mammalian classification, such basal features as 

 those comprised in the structure of the nose and lips, in the 

 tympanic and orbital regions of the skull, and in the genitalia 

 appear to justify the separation of Tarsius from the Lennu'oidea, 

 and warrant its inclusion in the Anthi'opoidea. But in several 

 very striking details Tarsius differs from all niembers of the 

 Anthropoidea except the very highest. In many characters 

 Tarsius resembles Homo and differs from the Monkeys, in some 

 it resembles Homo and cert-nn of the Anthropoid Apes. These 

 features are only to be termed primitive mammalian characters, 

 and as a result of summarising the anatomy of the Anthropoidea 

 it appears to me to be legitiniate to conclude that Tarsius and 

 Homo retain a remarkable series of primitive mammalian 

 characters, some of which are retained in part in the Anthropoid 

 Apes, but which are departed from increasingly widely as the 

 zoological scale of the Anthropoidea is descended, (i.) Tarsius 

 differs from all Anthropoidea except Man and the Orang in the 

 arrangement of the elements in the basis oranii ; hei-e it le- 

 sembles all primitive mammals, (ii.) It differs from all Anthro- 

 poidea, with the same two exceptions, in the normal retention of 

 the alisphenoid-parietal pterion. (iii.) In the digital and meta- 

 carpal formulas it shows a pi-imitive (and human) character in 

 avoiding the relative reduction of the 2nd digit of the manus 

 typical of the remaining members of the Anthropoidea. (iv.) In 



