24 ZOOLOGICAL GEOGRAPHY. [PART in 



developed. The central and most conspicuous figure is the collared 

 ant-eater, (Tamandua tetradactyla) , one of the handsomest of the 

 family, in its conspicuous livery of black and white. To the left 

 are a pair of sloths (Arctopitliecus flaccidus) showing the curious 

 black spot on the back with which many of the species are marked, 

 and which looks like a hole in the trunk of a tree ; but this mark 

 seems to be only found on the male animal. The fur of many of 

 the sloths has a greenish tinge, and Dr. Seemann remarked its 

 resemblance to the Tillandsia usneoides, or " vegetable horsehair," 

 which clothes many of the trees in Central America ; and this 

 probably conceals them from their enemies, the harpy-eagles. On 

 the right are a pair of opossums (Didelphys azarce), one of them 

 swinging by its prehensile tail Overhead in the foreground are 

 a group of howling monkeys (Mycctes ursinus) the largest of the 

 American Quadrumana, and the noisiest of monkeys. The large 

 hollow vessel into which the hyoid bone is transformed, and 

 which assists in producing their tremendous howling, is alto- 

 gether unique in the animal kingdom. Below them, in the dis- 

 tance, are a group of Sapajou monkeys (Cebus sp.) ; while gaudy 

 screaming macaws complete the picture of Brazilian forest life. 



Birds. A very large number of genera of birds, and some 

 entire families, are confined to this sub-region, as will be seen 

 by looking over the list of genera at the end of this chapter. 

 We can here only notice the more important, and summarize the 

 results. More than 120 genera of Passeres are thus limited, 

 belonging to the following 12 families: Sylviidae (1), Troglo- 

 dytidas (2), Coerebidae (4), Tanagridae (26), Fringillidae (8), Ic- 

 teridae (5), Pteroptochida3 (3), Dendrocolaptidae (12), Formi- 

 cariidse (16), Tyrannidae (22), Cotingidee (16), Pipridse (10). Of 

 the Picarise there are 76 peculiar genera belonging to 9 families, 

 viz., Picidae (2), Bhamphastidae (1), Cuculidae (1), Bucconidae 

 (2), Galbulidae (5), Momotidse (2), Podargidae (1), Caprimalgidae 

 (4), Trochilidae (58). There are 3 peculiar genera of Psittaci, 8 

 of Gallinae, the only genus of Opisthocomidae, 3 of Accipitres, 

 I of Ballidae, Psophia and Eurypyga types of distinct families, 

 and 1 genus of Ardeidae, Palamedeidae, and Anatidae respectively. 

 The preceding enumeration shows how very rich this sub-region 



