CHAP. XIV.] 
THE NEOTROPICAL REGION. 
23 
Having already given a sketch of the zoological features of 
the Heotropical region as a whole, the greater part of which will 
apply to this sub-region, vpe must here confine ourselves to an 
indication of the more important groups which, on the one hand, 
are confined to it, and on the other are absent ; together with a 
notice of its special relations to other regions. 
Mammalia. — Many of the most remarkable of the American 
monkeys are limited to this sub-region ; as Lagothrix , Pithecia , 
and Brackyurus, limited to the great Amazonian forests ; Eriodes 
to south-east Brazil; and CallitJirix to tropical South America. 
All the marmosets (Hapalidfe) are also confined to this sub-region, 
one only being found at Panama, and perhaps extending a little 
beyond it. Among other peculiar forms, are 8 genera of bats ; 
3 peculiar forms of wild dog ; Pteronura, a genus of otters ; 
Inia, a peculiar form of dolphin inhabiting the upper waters of 
the Amazon ; tapirs of the genus Tap ir us (a distinct genus being 
found north of Panama) ; 4 genera of Muridse ; Ctenomys, a genus 
of Octodontidae ; the whole family of Echimyidse, or spiny rats, 
(as far as the American continent is concerned) consisting of 8 
genera and 28 species ; Chcdomys, a genus of Cercolabidse ; the 
capybara ( ' Hydrochcerus ) the largest known rodent, belonging to 
the Caviidae ; the larger ant-eaters {Myrmecophaga) ; sloths of the 
genus Brady pus ; 2 genera of armadillos (Dasypodidse) ; and two 
peculiar forms of the opossum family (Didelphyidse). No group 
that is typically Neotropical is absent from this sub-region, 
except such as are peculiar to other single sub-regions and which 
will be noticed accordingly. The occurrence of a solitary species 
of hare ( Lepus braziliensis ) in central Brazil and the Andes, is 
remarkable, as it is cut off from all its allies, the genus not being 
known to occur elsewhere on the continent further south than 
Costa Pica. The only important external relation indicated by 
the Mammalia of this sub-region is towards the Ethiopian region, 
2 genera of Echimyidae, Aulacodes and Petromys , occurring in 
South and South-east Africa. 
Plate IV. Characteristic Neotropical Mammalia. — Our illustra- 
tion represents a mountainous forest in Brazil, the part of South 
America where the Neotropical Mammalia are perhaps best 
