276 bulletin: museum of comparative zoology. 



Nine species remain to be mentioned. Of these, two have been arti- 

 ficially introduced. They are Bufo marinus (Linne) and Elmtherodacty- 

 lus martinicensis (Peters). Besides these it is very probable that Gona- 

 todes albogularis (Dum. & Bibr.) has spread accidentally from Cuba. 

 The other gecko Aristelliger praesignis (Hallowell), which is not confined 

 to the island, should probably be included in the list of peculiar species ; 

 the species described from the islands off the Central American coast is 

 probably distinct, the ones on the Caymans were possibly carried there 

 by the turtling schooners. Anolis sagrae Dum. & Bibr. and Typhlops 

 lumbricalis (Linne) have a wide range through the West Indian region 

 and their distribution is hard to explain. As for Tropidophis maculata 

 (Bibron) I have refrained from defining its range. The Museum has 

 specimens from Haiti which are the same as the Jamaican ; we have, how- 

 ever, no Cuban examples, so that no evidence is available as to the simi- 

 larity of these with Jamaican specimens. Regarding the presence of the 

 fresh-water turtle Pseudemys palustris (Gmelin) and the crocodile Croco- 

 dilus americanus Laurenti there is nothing especially noteworthy. The 

 latter probably reached the islands by swimming and may do so still 

 occasionally, for crocodiles often get far out to sea. The turtle, however, 

 has doubtless been long established, and more material will very probably 

 prove the existence of island races evolved through isolation. 



Thus, in conclusion, we may say that the island has twenty-five 

 peculiar species. 



The derivation of the species is in most cases evident, and falls into 

 two groups, those which have come through the Lesser Antillean chain 

 from northeastern South America, and those which have come from directly 

 west. Dr. Stejneger in his careful resume of the origin of the fauna of 

 Porto Rico in his Herpetology of that island has shown that there the 

 first-mentioned group is strongly predominant. This is to be expected 

 from the geographical position of that island. In Jamaica the fauna is 

 almost wholly composed of genera or groups of species as Eleuthero- 

 dactylus, Celestus (derived from the Central American Diploglossi), Ma- 

 buia, Epicrates, which have reached the Greater Antilles from Central 

 America. As in Porto Rico the Sphaerodactyli and Anoles seem also 

 intimately related to forms from the West, and the single Ameiva 

 and the Typhlops suggest very strongly Lesser Antillean affinities. The 

 two species of Leimadophis are of a genus characteristically Antillean 

 and which doubtless developed on the once existing land mass almost con- 

 tinental in size. They suggest the joining of Jamaica to Antillea as 

 other species do the connection with Central America. A marked diver- 



