ALLEN: MAMMALS OF THE WEST INDIES. 189 



to both Greater and Lesser Antilles. These are Brachyphylla, Mono- 

 phvllus, and Ardops with its Cuban and Jamaiean offshoots, Phyllops 

 and Ariteus. The general distribution of these bats may indicate 

 that at one time the land area of the Greater and Lesser Antilles was 

 more or less continuous, or that the same genus reached the two groups 

 from Central and from South America respectively, and then spread 

 in both directions. The former supposition is the more probable, 

 and is borne out by the facts of the distribution of reptiles (Barbour, 

 1910). Other species whose distribution is continuous throughout 

 the Antilles are: Noctilio leporinus, Artibeus jamaicensis, Nyctinornus 

 brasilicnsis, and Molossus obscurus. Of these, all but the first are 

 represented by local races, a study of which tends to show that they 

 have reached the Antilles from both ends of the chain simultaneously. 



The distinctness of the mammalian fauna of the Greater Antilles 

 from that of the Lesser is very striking. The terrestrial species of 

 the former seem to be entirely derived from North and Central 

 America, while those of the Lesser Antilles are equally of South Ameri- 

 can affinity. The two faunae meet at the northeastern corner of 

 the Antillean chain. Similarly the bats of the two groups comprise 

 many genera or species peculiar to each. Thus Chilonycteris, Mor- 

 moops, Otopterus, Erophylla, Chilonatalus, Eptesicus, Lasiurus, 

 and Eumops are present on two or more of the Greater, but are 

 unknown from the Lesser Antilles. On the other hand, Peropteryx, 

 Pteronotus, Glossophaga longirostris, Artibeus planirostris grena- 

 densis, Myotis dominicensis, and Molossus erassicaudatus are Lesser 

 Antillean bats that have very clearly reached those islands from South 

 America, and are unknown in the Greater Antilles. The relations 

 of the Lesser Antillean islands to each other are apparently much sim- 

 pler than those of the Greater. Thus, the mammals of Tobago are 

 very similar to those of Trinidad, though fewer in species; and pro- 

 ceeding northward, the known species are all such as would be expected 

 to have come over a land bridge from northern South America. There 

 is also a diminution in the number of genera represented as one pro- 

 ceeds northward, although, owing to our imperfect knowledge, it is 

 still impossible to state this difference accurately. Dominica seems 

 to be the best known of any of the Windward Islands as regards its 

 bat fauna, but as yet only nine species are recorded. 



The former land connections and faunal migrations of what are 

 now the Greater Antilles seem to offer much more complex problems. 

 Thus, Cuba must have received accessions largely through a Yucatan 

 land bridge. Some also may have come from Florida by way of 



