FRESH-WATER FISHES— MYERS 355 



unknown. It is therefore pertinent to point out that finely spun 

 schemes of distribution based entirely on the living (or Pleistocene) 

 fauna are likely to receive rough treatment when and if good fossil 

 evidence is found. What is known of the fresh-water fishes of the 

 islands, though instructive, will of itself answer no important question 

 conclusively, and I shall therefore give only a brief and very sketchy 

 summary of one or two of the problems which the fishes may help us 

 to solve. 



Much has been published on West Indian zoogeography. For my 

 purposes, I refer only to Matthew (1915 and 1916), Barbour (1914 and 

 1916), Anthony (1918), Scharff (1922), Schmidt (1928), and Dunn 

 (1934). From the bibhographies of these papers some idea of the 

 other literature may be gained. 



Except for Matthew, most of these writers are rather definitely in 

 favor of a union of the Greater Antilles at some time during the 

 Tertiary, and a continental connection of this mass or one of its ele- 

 ments with the North, Central, or South American mainland at some 

 period from the late Mesozoic to the middle Tertiary. I admit that 

 the evidence these men present is both enticing and impressive. The 

 distribution of the amphibians is the most impressive to me, perhaps 

 because I am more familiar with that group than with other quad- 

 rupeds. Since the time of Darwin the natural occurrence of amplii- 

 bians on an island has been almost universally accepted as incon- 

 trovertible evidence that that island has had a continental land 

 connection. Amphibians are delicate creatures, extremely sensitive 

 to desiccation and to salt water, and since they do not possess wings, 

 it is difficult to imagme how they could possibly cross a body of sea 

 water by any natural means. The West Indies, especially the 

 Greater Antilles, are extremely well supplied with several genera of 

 amphibians. Indeed it would seem that one of the chief diversions of 

 contemporary American herpetologists is the describing of new West 

 Indian Eleutherodactyli! If I am not believed, I would refer my 

 questioner to Dr. Barbour's recent hst (1935). 



Against this evidence, the late Dr. Matthew has stood out prac- 

 tically alone in maintaining that the West Indies are true oceanic 

 islands in that they have never had a continental connection. He 

 holds that the entire terrestrial fauna of these islands is a waif fauna — 

 one gained entirely through fortuitous methods of dispersal such 

 as winds and drifting debris. It may be said that many biologists 

 are coming to appreciate that an island can pick up an astonishing 

 number of vertebrate and invertebrate animals in this manner. 

 Great tropical rivers continually carry floating masses of vegetation, 

 sometimes of considerable extent, out to sea, and all sorts of creatures 

 are known to have been floated away to no one knows what fate on 

 rafts of this type. It is certain that the populations of these rafts 



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