16 



BULLETIN 17 7, UNITED STATES NATIONAL MUSEUM 



A male (U.S.N.M. No. 74545) from Rio San Juan measures 

 61 mm. from snout to vent, and this seems to be about the maximum 

 size for males, the females averaging over one-fourth longer. The 

 males have very prominent external vocal pouches on each side of 

 the throat, while the inner surface of the thumb is an enlarged, black, 

 horny patch. Some of the females from Rio San Juan, taken in 

 March, contain heavily pigmented eggs of approximately the same 

 size as those of the described specimen taken in December. 



Occasionally a wider eyelid and a correspondingly narrower inter- 

 orbital width are found, but as a rule the eyelid is conspicuously small 

 in this species. 



Relationships. — Though it is obvious that the present species is 

 closely allied to the Cuban Hyla septentrionalis, the two are very 

 easily separable on leg length alone. The Hispaniolan form has the 

 tibiotarsal articulation reaching the tip of the snout, while the tibia 

 is more than half the distance from snout to vent. In the Cuban 

 form the tibiotarsal joint just reaches to the anterior corner of the 

 eye, while the tibia is less than half the length of the frog. The 

 interorbital width is noticeably less in the Cuban species, with a 

 corresponding increase in the size of the upper eyelid. 



Specimens examined. — As listed in table 4. 



Table 4. — Specimens of Hyla dominicensis examined 



