474 ON THE ZOOLOGICAL POSITION 



fossil reptiles which are distinguished from all other reptiles 

 (including all the surviving members of their Class) by a lai'ge 

 number of features which they share with Mammals. Moreover, 

 it is now generally admitted that the Mammalia were derived from 

 one of the Oynodont families. Yet no palaeontologist, so far as 

 I am aware, has been reckless enough to suggest that the 

 Cynodonts should be removed from the Class Reptilia and pro- 

 moted to the Class Mainmalia. But those who want to remove 

 Tarsius from it slowly station and elevate it from Prosimian 

 to Simian rank are making a claim that is as preposterous as 

 the hypothetical parallel just suggested. Tn some respects the 

 analogy may seem inconsistent with the course I have adopted 

 here. It may perhaps be argued that, just as the Cjaiodonts are 

 still I'etained in the Class Reptilia, so the Tarsioids ought to be 

 retained in the Suborder Lemui'oidea. Matthew and Gregory 

 have, in fact, recently {op. cit. sup7'a) reaffirmed their belief in 

 this traditional method of subdividing the Primates; and there 

 is unquestionably a good deal to be said for preserving the term 

 Prosimise. But the problem difiers from that of the Cynodonts 

 in that we are now discussing the grouping of the constituent 

 parts of a single Mammalian Order, whereas the Cynodont 

 problem involves the interrelationships of two Vertebrate Classes. 

 The depth of the cleavage between the Tarsioids and the 

 Lemuroids and the remarka,ble affinities of the former to the 

 Anthropoidea signifies that the Tarsioidea occupy a position 

 definitely intermediate between the othei' two groups of Primates, 

 which finds most natural and most convenient expression if 

 a separate Suborder is made to include the Tarsioids. This is no 

 mere compromise between the extremists on the two sides, but 

 the arrangement which the whole trend of research since the time 

 of Burmeister has made more and more insistent and necessary. 



If the exact status and affinities of the Tarsioidea as Eocene 

 Prosimife and their little-altered survivors has been definite!}" 

 established, the recent discoveries* of the Early Oligocene genera 

 Parapiihecus and Pro2Mo2yithecus in the Egyptian Fayum have 

 no less definitely settled the relationships of the Suborder to the 

 Anthropoidea.. Farapiihecns retains sufficient of the primitive 

 traits to establish the tmith of the Tarsioid ancestry of the Apes, 

 but it also provides evidence which can only be adequately 

 explained on the supposition that the transformation of a 

 Tarsioid into a primitive Ape must have occurred before the 

 close of the Eocene. For in the lowest Oligocene the primitive 

 ape Parapithecus is found in association with Propliopithecus, 

 which had developed far beyond the stage represented by the 

 former and become a real Anthropoid Ape. Parapithecus, then, 

 at the beginning of the Oligocene, must have been a survival from 



* M. Sclilosser, " Beitrage z.ur Kenntniss der Oligozaiien Landsaugetiere aus dein 

 Fayum (Agypteii)," Beitrage 7,ur Pal. u, Geol. Osterreicli-Ungarns w. d. Orients, 

 Bd, xxiv. 1911, p. 52, 



