190 bulletin: museum of comparative zoology. 



another land connection. Such, for example, is probably Megalonyx, 

 and perhaps the bat genus Nycticeius. A more intimate knowledge 

 of the fauna of San Domingo is imperative for the determination of 

 the extent to which migration took place between that island and 

 Cuba. There is evidence that the connection became dissolved before 

 that with Yucatan. This might account for the apparent isolation 

 in Cuba of Megalonyx, the long-tailed species of Capromys, and the 

 bats Nycticeius, Nyctiellus, Mormopterus. Perhaps also the appar- 

 ent absence of a race of Eptesicus fuscus from the other islands (? except 

 Bahamas) is explicable through the short duration of a Cuba-San 

 Domingo connection. 



Notwithstanding the number of evident similarities between the 

 fauna of- Cuba and that of Jamaica, these need not indicate any direct 

 land connection between the two islands. Indeed, the evidence seems 

 to point to their long isolation. Of the bat genera common to both, 

 Chilonycteris, Mormoops, Otopterus, Chilonatalus, Lasiurus, Nyc- 

 tinomus (Nyctinomops group), and Eumops are not known from the 

 Lesser Antilles. Two species of Chilonycteris occur together on both 

 Cuba and Jamaica, as well as on other of the Greater Antilles. Both 

 have probably reached these islands through separate land connec- 

 tions by way of Yucatan and the Honduras peninsula respectively; 

 and by a similar route it is probable that the other genera came to 

 each. Evidence for this assumption is the apparent absence in Cuba 

 and other of the Greater Antilles of the three following bats known 

 in Jamaica: Vampyrus spectrum, Hemiderma perspicillatum, and 

 Sturnira lilium. Probably the range of these tropical species never 

 extended sufficiently far north to permit of their crossing by a land 

 bridge to Cuba by way of Yucatan, whereas it did allow of their 

 reaching Jamaica by way of the supposed Honduras land tongue. 

 We may assume, further, that the connection with San Domingo 

 had disappeared by the time they reached Jamaica. 



The genus Phyllonycteris of Cuba may be represented in Jamaica 

 by the endemic Reithronycteris, just as Phyllops of Cuba seems 

 to be represented by Ariteus in Jamaica. The fact of these genera 

 having been thus independently developed on the two islands from 

 some common stock seems to indicate a long isolation. 



On the other hand, there are several species which are practically 

 identical on the two islands. Thus, Chilonatalus micropus of Jamaica 

 is considered the same as that of Cuba; Nyctinomus b. muscuhis and 

 N. macrotis are the same on both; and the Eumops of Cuba, con- 

 sidered the same as E. glaucinus of the mainland, is not greatly 





