HERPETOLOGY OF PORTO RICO. 565 



The number of species occurring- in St. Thomas and St. John but 

 not in Porto Rico proper are very few, as shown in the following: 



List of species occurring in St. Thomas (") and St. John but not in Porto Rico proper. 



5. Amphisbaena fenestrata. 



6. Leimadophis exiguus. 



7. Alsophis antillensis. 



1. Eleutherodactylus lentus. 



2. Eleutherodactylus antUlensis. 

 :'>. Sphaerodactylus macrolepis. 



4. Iguana iguana. 



It will be seen in every case but one that these represent species living 

 in Porto Rico, and, moreover, that three of them extend so far west 

 as to include Vieques and Culebra, namely, Eleutherodactylus antil- 

 lensis, Leimadophis exiguus, and Alsophis antUlensis. The only spe- 

 cies which is not represented at all in Porto Rico is Iguana iguana, 

 and it is altogether probable that this species has been introduced 

 originally by man. 



As an offset to the three peculiar Virgin Island species mentioned 

 above, which extend as far west as Vieques, we may mention for the 

 sake of completeness a Porto Rican species which reaches Tortola, but 

 which has not been recorded from St. Thomas or St. John, namely, 

 Anolis cuvieri. 



It is then plain that the sixteen species of reptiles and batrachians 

 found in St. Thomas and St. John 6 form only a herpetological appen- 

 dix to Porto Rico. 



VERTICAL DISTRIBUTION. 



With regard to the vertical distribution of the batrachians and rep- 

 tiles in Porto Rico it must be borne in mind that the island, although 

 very mountainous, does not rise to such great altitudes as the other 

 Greater Antilles. The El Yunque Mountain, which has been consid- 

 ered the highest point in Porto Rico, has lately been determined to be 



«Only such species are included the occurrence of which is corroborated by 

 repeated finds, and consequently undoubted. 



''1. Leptodaetylus aUnlabris. 



2. Eleutherodactylus antillensis. 



3. Eleutherodactylus lentus. 



4. Thecadaclylus rapicauda. 



5. Semidactylus mabouia. 



6. Sphaerodactylus macrolepis. 



7. Mabuya sloanii. 



<S. Ann i in exul. 



9. Anolis cristateUus. 



10. Anolis stratulus. 



11. Anolis pulchellus. 



12. Iguana iguana. 



13. A mphisbsena fenestrata. 



14. Typhlops luinhricalis. 



15. Leimadophis exiguus. 



16. Alsophis antUlensis. 



A number of species credited to St. Thomas on the strength of uncorroborated 

 museum labels is here left out. It is not unusual that museum specimens are cred- 

 ited to the place from which they were shipped, which may have been another than 

 the one in which they were collected. On the other hand, single specimens acci- 

 dentally introduced from near-by islands may well be expected in a place like St. 

 Thomas. 



