342 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



■ Distribution. — James, Jervis, Indefatigable, South Seymour 

 and Barrington Islands, Galapagos Archipelago. 



Material. — Five specimens collected by Dr. Habel, probably 

 on Indefatigable or Jervis Islands, are in the Vienna Museum. 

 I have examined fifty-one specimens in the Academy collec- 

 tion, as follows : twenty-three from Indefatigable, fifteen from 

 Barrington, eight from James, three from South Seymour, 

 and two from Jervis. 



Description of No. 12062. — Adult male. Indefatigable Island. J. R. 

 Slevin. July 16, 1906. 



Head fairly broad, with flattened top and rounded snout. Rostral plate 

 large, much broader than high, hollowed below, and bounded behind by 

 internasal, anterior nasal and first labial plates. Plates on top of head 

 are : a pair of internasals, a pair of prefrontals, supraocular and part of 

 preocular of each side, a frontal, and a pair of large parietals. Internasals 

 smaller than prefontals. Frontal longer than parietal suture. Anterior 

 and posterior nasals distinct. Loreal well developed, little longer than 

 high. One preocular. Two postoculars. Temporals one followed by two. 

 Eight superior and ten inferior labials, sixth upper and fifth or sixth lower 

 largest, fourth and fifth upper reaching eye, first pair of lower meeting on 

 median line. Genials in two pairs, posterior a little longer, anterior touch- 

 ing five labials. Scales on body smooth, many with pits, in nineteen rows. 

 Anal plate divided. Gastrosteges two hundred and twenty. Tail complete. 

 Urosteges one hundred and thirteen, the second to seventh undivided. 



The upper surface of the head is yellowish olive dotted with brown. 

 There is a brown band from the rostral to the eye and from the eye to 

 the side of the neck. The labials, chin, and throat are yellowish white 

 dotted with dark brown. The body is longitudinally striped. The lower 

 three (or, on the posterior part of the body, two) rows of scales are gray- 

 ish brown. The next row is dark brown. The fifth, sixth, and seventh 

 rows are yellowish white. The eighth row is dark brown, and the three 

 rows along the middle of the back are lighter olive brown. The stripes 

 are continued on to the tail, but the distal portion of this region is plain 

 yellowish olive. The lower surfaces are yellowish white irregularly dotted 

 and spotted with dark brown. 



Length to anus, 670 mm. 

 Length of tail, 248 mm. 



Variation: Indefatigable Island. — Only two specimens 

 (Nos. 10233 and 10796) have all the urosteges divided. 

 Some specimens have only the second urostege undivided. At 

 the other extreme is No. 10232 in which the second to twenty- 

 second, forty-fifth to forty-eighth, and sixty-third to sixty- 

 fifth, are unpaired. The urosteges range from one hundred 

 and five to one hundred and nineteen, and the gastrosteges 

 from two hundred and seventeen to two hundred and thirty. 



