66 PKOCEEDINGS OP THE ACADEMY OP 



colored, the denticulations and tubercles of the palms and toes tipped with 

 brown. Total length, 20 in. ; head and body to vent 6 in. 6 lin. 



Hab. St. Thomas. Santa Cruz, Porto Rico; according to the Erpetologie 

 Generale, Martinique and Hayti. Mus. Philadelphia Academy. Smithsonian. 

 Compar. Zoology, Cambridge. 



Two specimens from Porto Rico have the lateral blacks spots larger, with a 

 trace of a superior series posteriorly. In this animal the adult presents but 

 three obtuse-crowned median maxillary teeth. This difference between the Porto 

 Rican form and that of St. Thomas appears of importance when we recollect the 

 relation which exists between the genera Ameiva and Tupinambis (Teius Gr.) 

 in this respect. Indeed, although the present species is closely allied in super- 

 ficial characters to the A. auberi and thoracica, were it not for the re- 

 pressed development just alluded to in its Porto Rican form, it would appear 

 proper to regurd the significance of this dentitional peculiarity as fully generic. 

 Should the Porto Rican form begin to develop cylindrical and obtuse-crowned 

 teeth at an earlier age, so as finally to exelude the compressed tricuspid, this 

 peculiarity would become the index of a definable generic group; or should 

 the time of the appearance of these teeth be finally postponed to a period beyond 

 the usual limit of life, the same separation would be the result, the Porto Rican 

 form remaining as a distinct species of Ameiva. The anatomical relation be- 

 tween these lacertian forms is certainly identical with that existing between 

 Protonopsis and Megalobatrachus, Siredon and Amblystoma; and if a gene- 

 ric connection between the former can be reasonably suspected, (and geo- 

 logical as well as morphological considerations support this view), it might be 

 as justly inferred in the case of the latter. The largest shields of the external 

 tibial series reach a considerable development in the Porto Rican specimens; 

 hence I have suspected the Ameiva scutata of Dr. Gray might belong here. 

 One or two of the St. Thomas specimens exhibit a development of these plates 

 fully equal. Whether all belong to the true A. plei Dum. & Bibr., can only 

 be settled by those who can compare Martinique specimens with those from the 

 localities in question. 



Var. e x s u 1 . 



This form differs in possessing a narrow bright yellow band on each side, 

 extending from the superciliary ridge to a point on the anterior part of the tail. 

 The anterior extremity extended backward exceeds the extremity of the ap- 

 pressed femur. Total length 7 in. G lin. ; exclusive of tail, 2 in. 1 lin. (Pro- 

 bably young.) 



Hab. Water Island. Mus. Smithsonian. 



A. po 1 o p s Cope. 



Seven or eight marginal supraorbitals. Median gular scales little larger 

 than the lateral ; scales of the neck-fold moderate. One large and several 

 small series of antebrachial plates not continuous with the short brachial 

 series ; postbrachials distinct. Preanals in two parallel longitudinal series. 

 Femoral plates numerous ; pores nineteen. Tibial series two, the internal 

 small; the external composed of seven plates, fourth largest, third next. Ex- 

 ternal digit extending much beyond the internal. Above olive brown; a 

 brownish black band, anteriorly light bordered above, extends from the 

 superior border of the auricular opening to the crural region. This is bordered 

 beneath by a narrow light line which terminates above the femur. Below this 

 is a brown band, whicb is separated from a brown line on the exterior belly 

 plate by a narrow yellow line. Tibia with an anterior light line. Femora 

 behind light banded continuously with the tail. The latter member appear? 

 to be faintly annulated. Belly light greenish. Total length 1 in. 2 lin. ; ex- 

 clusive of tail, 2 in. 6 lin. 



Hab. St. Croix, West Indies. Mus. Smithsonian. 



[Feb. 



