GEOGRAPHICAL DISTRIBUTION AND DESCENT. 



73 



toward strangers, and would climb up to his head 

 a dozen times in the course of an hour, making 

 a great show every time of searching there for 

 certain animalcula." — Bates, The Naturalist on the 

 River Amazons, vol. i. chap. iii. 



The species most frequently to be seen 

 among us are the bushy -eared monkeys, 

 known under the name of Ouistiti or Common 

 Marmosets. Fig. 24 represents the com- 

 monest of the species so called {Hapaie 



Jacchus). This little creature attains at 

 most a length of 91^ inches, while the thick- 

 haired tail with dark rings is about one- third 

 longer. The distinguishing character of 

 these animals consists in stifif tufts of hair in 

 front of the ears, these tufts being mostly 

 divided into three parts, and generally of 

 a bright colour. In the species represented 

 these tufts are white, while the body has a 

 grayish or dark slate-colour. 



GEOGRAPHICAL DISTRIBUTION AND DESCENT OF THE 



APES AND MONKEYS. 



The geographical distribution of apes and 

 monkeys presents many remarkable pecu- 

 liarities worthy of a closer consideration. 



With few exceptions, belonging chiefly to 

 the Semnopitheci and the Cynocephali, 

 found on the high mountains of Asia and 

 Africa, even in some cases on the edge of 

 the snow-line, all monkeys are to be found 

 within the tropical and subtropical zone in 

 which palm-trees flourish. The palms have 

 even a wider area of distribution in lati- 

 tude, for while the magot is indeed settled on 

 European soil in company with the dwarf- 

 palm of the Mediterranean region, monkeys 

 are altogether wanting in the palmetto re- 

 gions of Texas and Louisiana. On Mada- 

 gascar and the Antilles also monkeys do not 

 occur, although these islands are rich in 

 palms. As regards elevation, however, 

 monkeys have the advantage, for in the 

 Himalayas and in Northern Tibet monkeys 

 are met with even in the pine forests of the 

 higher regions, which are covered with snow 

 for months together. 



This law of confinement to tropical and 

 subtropical climates appears to have been 

 universally valid also in former geological 

 epochs. The primitive monkeys pressed 

 much farther northwards, but during epochs 



when palms also extended to the shores of 

 the Baltic and the south coast of England. 

 When the Thames flowed in regions whose 

 climate, to judge from the plants found in 

 them, resembled that of the region intersected 

 by the mouths of the Ganges, monkeys oc- 

 curred even in the latitude of London. The 

 largest and most human-like monkeys are 

 found only in the hottest regions of the Old 

 World, and an ancestor of these, the Dryopi- 

 thecus, lived in southern France during the 

 Miocene period as member of a fauna 

 analogous to that of the torrid zone in the 

 present age. 



Of special importance is the sharp separa- 

 tion between the monkeys of the Old and the 

 New World, those of the Indo- African tropics 

 on the one side, and those of the South 

 American tropics on the other, a separation 

 which is unequivocally expressed in the 

 zoological characters, and culminates in this, 

 that the Simiae of the Old World, by the 

 structure of their nose and teeth, as well as 

 by their adaptation to more varied conditions 

 of life, have unquestionably attained in their 

 branches a higher stage than their American 

 kindred. All the American Platyrrhines with 

 36 teeth, and all the Clawed Monkeys, are 



arboreal forms, and so much dependent on 



10 



