564 REPOET OF NATIONAL MUSEUM, 1902. 



7. Typhi ops himlyricalis. 



8. Ep'icmtes monensis. 



9. Ahoj)hls portoricensis. 



These also show a mixture of types. Ahophis portoricensis is tj^p- 

 ical Porto Rican; SpJtxrodactylus monen.ds^ Ameiva aJhoguttata^ and 

 Anolis monensis, although described as separate forms, are very closely 

 allied to Porto Rican species; Mahuya sloanii occurs both in Porto 

 Rico and Haiti; Eleatlierodactylus inonenslt^ and Ep>icratts monensis ^yq 

 most nearly related to Haitian species, while Cye-liira cornuta is typ- 

 ically Haitian, the o-enus even being unknown in Porto Rico; Typhlops 

 lumhricaJis is of wide distribution, as shown above. The herpetolog- 

 ical fauna of Mona is consequently exactl}^ intermediate between Porto 

 Rico and Haiti, as is its geographical position. 



The herpetological relations of Porto Rico to the Virgin Islands 

 immediately to the east is very close, as might be expected, located, as 

 they are, within sight of each other and on the same bank limited by 

 the lOU-fathom line. St. Croix, which is separated by a deep channel 

 from the others, is also more distantly related, possessing, as it does, 

 several species not found in the Virgin Islands proper, much less in 

 Porto Rico, namely, Thecadactyl us rapicauda (possibly accidentally 

 introduced), Anolis actitus, Ameiva polops, and Alsophis sancti-crucis. 



If we compare the fauna of Porto Rico with that of St. Thomas and 

 St. John more in detail, we will lind that the chief difference lies in the 

 absence in the latter of a great number of species occurring in the 

 former, as will be seen from the following: 



Lht of Porto Rican species («) not found in St. Tliomas or St. John. 



1. Bufo lemur. 



2. Eleutherodactijlus auricnlatus. 



3. Eleutherodactylus richmondi. 



4. Eleutherodactylus unicolor. 



5. Sphperodactylus grandisquamis. 



6. Celestus pleii. 



7. A.nolis cuvieri. 



8. Anolis gmidlachi. 



9. Anolis evernianni. 



10. Anolis krugi. 



11. .1 nolis poncens is. 



12. Amphishwna cseca. 



13. Amphisbeena bakeri. 



14. Typhlops rostellatus. 



15. Epicrates inomatus. 



16. Leimadophis stahli. 



17. AlsopJiis portoricensis. 



It will be seen that the existence of many of these species in Porto 

 Rico is not due solel}^ to the fact that it is much the larger island, but 

 also to its more Avestern location and more intimate relation to the 

 other large Antilles. On the other hand, some of the species in 

 this list are represented in the Virgin Islands by very closely related 

 forms. 



aExcludiiiii those found in Mona Island. 



