GEOGRAPHICAL DISTRIBUTION AND DESCENT. 



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according to hemispheres, as it now exists, 

 was indicated from the first: all the fossil 

 remains of Simise hitherto found in the strata 

 of the Old World belong to the Catarrhines 

 with 32 teeth; all the New World bones, on 

 the other hand, to Platyrrhines with 36 teeth. 

 From the beginning of the Miocene, and 

 probably even earlier, the two hemispheres 

 were accordingly at least so far separated 

 that no transmigrations of monkeys could 

 take place. Similarly the absence of monkeys 

 on Madagascar proves that that large African 

 island has been separated from the mainland 

 since monkeys have existed, while, on the 

 other hand, the close ag-reement between the 

 monkeys of the Sunda Islands and those of 

 the neighbouring part of the Asiatic continent 

 must force on us the conviction that these 

 lands, now separated by arms of the sea, 

 must have been in connection with one 

 another down to comparati^'ely recent geologi- 

 cal epochs. The two simian stems, that of 

 the Old World and that of the New, must 

 accordingly have developed in isolation from 

 one another, and cannot be traced back to a 

 common root. 



We ha^•e already mentioned that, in ac- 

 cordance with the extension of warm climates 

 towards the north, to which the vegetable 

 world bears witness, the areas of distribution 

 of monkeys also extended northwards into 

 what is now Temperate Europe and the 

 north of the present United States. Judging 

 from the abundant remains that have been 

 discovered, especially at Pikermi in Greece 

 and Sansans at the foot of the Pyrenees, as 

 well as in Italy, we may conclude that in the 

 later Miocene period the belt bordering the 

 Mediterranean on the north must have been 

 inhabited by just as numerous herds of 

 monkeys of various species as the wooded 

 regions of the tropics in the interior of the 

 continents now are. 



Some facts appear to indicate that the 

 extinct monkeys of the Mediterranean region 

 belong more to the types now found in Asia, 



and exhibit characters combined which at 

 the present day are seen distinct and in a 

 more pronounced form in individual families 

 and o;enera. Thus, as Gaudrv has shown, 

 the monkey which has lett behind such 

 abundant remains at Pikermi (Mesopithecus) 

 is a Semnopithecus as regards the structure 

 of its head and the form of its teeth, while on 

 the contrary the bones of the body would 

 cause us to refer it to the macaques. This 

 mixture of characters, which afterwards be- 

 came more and more fixed so as to mark 

 off different divisions more sharply, is a 

 phenomenon of very common occurrence, 

 which we shall frequently, and indeed almost 

 universally, meet with hereafter in the various 

 orders of the Mammalia. The older type 

 is neither macaque nor Semnopithecus, but 

 possesses certain characters of both ; only in 

 the present geological epoch have these char- 

 acters become so pronounced as to charac- 

 terize different genera. One can trace the 

 magot from this separation. 



But this again is the only circumstance 

 that could be adduced in the case of the 

 Simla; as favouring the idea of a gradually 

 advancing development of the types. If we 

 consider the present Old World forms as 

 regards their divisions, Semnopitheci, Cerco- 

 pitheci, and Colobi might be taken as form- 

 ing the leading types for both continents, all 

 these being purely arboreal forms, intelligent 

 climbers, typical monkeys in every respect. 

 In the macaques on the one hand, and the 

 baboons on the other hand, we find adapta- 

 tions to a terrestrial mode of life represented, 

 in the gibbons and the other Anthropo- 

 morphae higher developments towards the 

 hurhan type. Attention has already been 

 drawn to the fact that these anthropoid apes 

 ascend towards the human type in different 

 directions, that accordingly, as I have already 

 clearlv shown a considerable time aofo, no 

 single line of ascent to the human type can be 

 demonstrated; that the gorilla stands nearer 

 to man than its rivals in respect of the struc- 



