Barbour — Notes on the Herpetology of the Virgin Islands. 101 



much larger, smooth and imbricating; on the nuchal region, a peculiar 

 fleshy fold hanging far over on the right side of the neck, no nuchal 

 spines ; series of dorsal spines beginning well posterior to the scapular 

 region, spines 33 in number, highest spines about 10 from posterior end 

 of series, about 1.5 cm. high; series widely interrupted upon the sacral 

 region ; caudal crest consisting of about 12 spines which grow progres- 

 sively smaller from the first to the last spine; upper surfaces of limbs 

 with many series of large diamond-shaped, feebly keeled scales; about 

 15 femoral pores on each side; toe combs as in stejnegeri and nigerrima; 

 tail slightly compressed, with segments very poorly denned ; each con- 

 sisting of a short incomplete row and three complete rows each progres- 

 sively slightly larger in size ; distal portion of the tail with a feebly serrate 

 crest of low tubercular scales. 



Color in life, brownish gray, on the limbs and tail in patches where 

 the skin has recently shed there are bright blue spots each limited to a 

 single scale. 



Mr. Peters heard of the Rock Iguana soon after his arrival upon Ane- 

 gada but had no success in securing specimens. He reports them exces- 

 sively rare, an occasional track in the sand being the only evidence of 

 their presence. This island with others near by has suffered terribly from 

 recent hurricanes and the forest or scrub laid low makes getting about 

 the uncleared and uncultivated parts of the islands very difficult, as this 

 wind-blown vegetation has had no time as yet to decay. It was only 

 when Peters found an old iguana hunter who had a dog that finally he 

 was able with extreme difficulty to secure the single living example, now 

 before me. He heard nothing of its existence or persistence in the other 

 islands which he visited, but there can be no doubt that it was previously 

 generally distributed. 



Iguana rhinolopha Wiegmann. 



A single immature specimen apparently referable to this species was 

 given Mr. Peters by S. Mailing-Holm, Esq., who captured it several years 

 ago upon Water Island. Iguanas have been recorded from St. Thomas, 

 Saba, Nevis, and various other islands nearby, sometimes as this species 

 and sometimes as delicatissima. Both species occurred, perhaps even on 

 the same islands. They were most probably introduced as food by pre- 

 historic man ; there can be little doubt from the nature of their distribu- 

 tion that their dispersal was either deliberately artificial or fortuitous. 



Serpentes. 



Alsophis antillensis (Schlegel). 



Three specimens from Virgin Gorda vary inter se in the intensity of the 

 variegated dark brown dorsum, but in all of them the fifth vertebral row 

 of scales has many of its components parti-colored— half whitish and 

 white black, as is characteristic of the species. Peters did not secure 

 Lemiadophis except upon Porto Rico, where he caught two examples of 

 L. stahli Stej. 



