Chap. V. BATS. 331 



antiquity. It is interesting to trace how the diversi- 

 fication of forms (if the expression may be allowed), 

 since the separation, has gone on in Tropical America. 

 What wide divergence as to size, forms, habits, and 

 mental dispositions, between the silver marmoset so 

 small that it may be inclosed in the two hands, and 

 the strong and savage black Howler, nearly two feet 

 and a half in length of trunk ! Yet there has been no 

 direct advance in the organisation of the order towards 

 a higher type, such as is exhibited in the old world. 

 America, for her share, has produced the most per- 

 fectly arboreal monkey in the world ; but beyond the 

 perfection of the arboreal type she does not go. The 

 retention of arboreal forms throughout long geological 

 ages, may teach geologists that there must always 

 have been extensive land areas covered by forests 

 on the site of the tropical zone of America. It is 

 curious to reflect, in conjunction with the fact of the 

 advance of the American Quadrumana having halted at 

 a low stage, that ethnologists have almost unanimously 

 come to the conclusion that the race of men now in- 

 habiting the American continent are not Autochthones 

 of America, the land of the Cebidse, but immigrants 

 from the Old World continent, the land of the Anthro- 

 poid group of the order Quadrumana. 



Bats. — The only other mammals that I shall mention 

 are the bats, which exist in very considerable numbers 

 and variety in the forest, as well as in the buildings of 

 the villages. Many small and curious species living in 

 the woods, conceal themselves by day under the broad 

 leaf-blades of Heliconiae and other plants which grow 



