70 THE NEOG^EIC REALM. [CHAP. 



teeth is 36, owing to the retention of the three pairs of molars 

 found in the Old World group ; these monkeys being further dis- 

 tinguished from the marmosets by the presence of nails on all the 

 fingers, and by the tail being frequently prehensile. The Santa 

 Cruz beds have yielded remains of monkeys (JFTomunculus) refer- 

 able to this family, showing that they belong to the original South 

 American fauna, but beyond this nothing is known as to the 

 palseontological history or origin of the group. Lemurs, both in 

 the past and the present, are quite unknown in the realm under 

 consideration. 



Although bats might be thought of comparatively little im- 

 portance from a distributional point of view, yet the 



Bats. :_ 



Neogseic realm presents some very remarkable 

 features in this respect. In the first place the two Old World 

 families of fruit-bats (Pteropodtdce) and horse-shoe bats (Rhinolo- 

 phidce] are entirely wanting, whereas the great family of vampire- 

 bats (Phyllostomatida) is mainly restricted to it, although a few 

 representatives straggle northwards along the Pacific coast of 

 North America. The family of Emballonuridtz is also more 

 strongly represented here than in any other part of the world. 

 Probably on account of their small size, there is no palaeonto- 

 logical record of the South American bats from the earlier 

 Tertiary deposits. 



The Insectivora are almost unrepresented in the continental 

 portion of the realm, although a shrew (Sorex) 



Insectivora. ' . 



reaches Guatemala and Costa Rica, and a member 

 of the allied N. American genus Blarina is also found in the 

 last-named country; both these being doubtless very recent 

 immigrants from the north. Very remarkable is the occurrence in 

 the West Indian Islands of the two species of Solenodon, consti- 

 tuting a distinct family (Solenodontidce) by themselves. These 

 have generally been considered as very nearly allied to the tenrecs 

 (Centetidce) of Madagascar, but Mr O. Thomas 1 is of opinion 

 that the relationship is not really very close, the similarity in the 

 structure of their molars being merely a generalised character. 

 Both, however, probably indicate an ancient group, which has 



1 Proc. Zool. Soc. 1892, p. 500. 



