316 BARBOUR: ZOOGEOGRAPHY. 



tions : — Some specimens show traces of a light, dark-bordered lateral line on the 

 body, in several this is fairly distinct on the tail. There is considerable variation 

 in the supralabials ; in one, the fifth and sixth are of about equal size and slightly 

 larger than the third. This specimen has but five infralabials. 



This species may be distinguished from S. cuvieri (Dum. & Bibr.) by the 

 possession of any one or more of the following characters (they may not all be 

 unvarying or equally diagnostic in the same individual) : — The frontal is usually 

 distinctly longer than broad; the last supralabial is not the largest; there are 

 more than four infralabials; the dark-bordered light Une is almost never present 

 on the body, but it may be evident on the tail. Dumeril and Bibron (Erpet. 

 gen., 1839, 5, p. 455) speak of seven upper labials of which the fifth is a scalene 

 triangle ; in S. alleni the fifth is pentagonal. Boulenger mentions but six upper 

 labials; it is somewhat difficult to determine just where labials end and contour 

 scales begin. Again, Dumeril and Bibron characterize the Colombian speci- 

 mens as having twenty-six rows of scales, and six rows of ventrals. Boulenger, 

 Garman, and I all agree on twenty-eight rows about the middle of the body. 



Except Trinidad, Grenada is the only island in the West Indies where this 

 genus is found. 



Scolecosaurus trinitatis, sp. nov. 



Type: — No. 8,947, M. C. Z., an adult, Caparo, Trinidad, A. B. Carr, 

 collector. Found under fallen cocao pods. Eight paratyi^es bear the same 

 data. 



The collection given recently by Professor Thaxter contains nine of these 

 lizards from Trinidad and ten from Grenada. For the first time it is possible to 

 compare a series from these islands. They represent a new species closely re- 

 lated, both seeming to differ in the same manner from the Columbian S. cuvieri. 

 In describing the previous species I have pointed out these different characters. 

 In Grenadian specimens the prefrontals, form a short suture, this is the condi- 

 tion which the published records also indicate for the mainland specimens. 

 The specimens from Trinidad, on the other hand, seem to have the prefrontals 

 invariably well separated, and not forming a suture. The series of nine all show 

 this condition. Thus, even if it should not prove to be absolutely constant it is 

 at least the characteristic condition and as the opposite seems equally constant 

 in the Grenadian specimens, the Trinidad form is entitled to specific rank. 



