ALLEN! MAMMALS OF TIIL WEST INDIKS. 187 



gua? The status of this rare bat is still somewhat in doubt. Miller, 

 in 1897, considered it a race of E. fuscus, but at the same time ex- 

 pressed the opinion that it might prove to be a distinct species. If 

 the latter view be accepted, it would be possible to assume that the 

 Bahama brown bat reached its present home by way of a land con- 

 nection from Honduras to Jamaica and San Domingo. Further 

 information as to the bat fauna of the latter island may throw light 

 on this question. 



It is remarkable that the genus Nycticeius, found elsewhere in 

 America over the southeastern United States only, should also occur 

 in Cuba. The recent discovery of a bat in East Africa, pronounced 

 by Mr. G. S. Miller a typical Nycticeius, is of extraordinary interest 

 in this connection. It is a fact probably quite in line with the presence 

 of the molossoid genus Mormopterus in Cuba, Peru, and southeastern 

 Africa, Madagascar, and Mauritius. A similar case is perhaps that 

 of the occurrence in British East Africa of the bat genus Laephotis, 

 nearly identical with the South American Histiotus. These and 

 other facts point strongly to the conclusion that there was formerly 

 a land connection between Africa and eastern South America, by 

 means of which such an interchange of tropical genera was made 

 possible. This view is ably supported by von Ihering from a study 

 of marine littoral molluscs of the Tertiary and Cretaceous. Ortmann 

 (1910) has recently reviewed his work, and writes that "the Arch- 

 heleriis-theory of von Ihering has now received so much support from 

 various sides that we may regard it as firmly established with regard 

 to its general correctness. Stated in broad terms, this theory assumes 

 a former land connection between Africa and South America, which 

 is rather old. This connection is the last remnant of a large southern 

 continental mass (South Atlantis, Gondwana-land), which existed 

 since the beginning of the organic history of the earth (Cambrium), 

 which was broken to pieces at different times, and the remnants of 

 which are now found in Australia, India, Africa and Brazil. The 

 separation of Brazil from Africa was the last step in the dismember- 

 ment of this old continent, an event which is placed by most writers 

 toward the end of the Mesozoic era, although some have admitted 

 the possible continuation of Archhelenis into the beginning of the 

 Tertiary." Ortmann disagrees with von Ihering's conclusion that 

 this land connection persisted into the Eocene. 



The evident relationship of Solenodon to the West African Potamo- 

 gale and the Madagascan Centetes may also point to a community of 

 origin and a continuity of habitat in the past. But it is not necessarily 



