Vol. II, Pt. I] VAN DENB URGH—SLEVIN—GALAPAGOAN LIZARDS 165 



teen from Charles Island, twenty-seven from Gardner-near- 

 Charles, sixteen from Champion, and thirty-one from En- 

 derby. Of these, one male and fourteen females from Charles, 

 thirteen males and fourteen females from Gardner, seven 

 males and nine females from Champion, and thirteen males 

 and eighteen females from Enderby are included in the tables 

 of scale counts. 



Description of adult male No. 9536. — The head is covered above with 

 smooth scales; interparietal largest, broader than long; four or five large 

 supraoculars ; superciliaries imbricate ; five superior and five inferior labials, 

 to below middle of the eye ; rostral very broad and low ; symphyseal 

 broad, followed by a series of large sublabials, of which all but the first 

 are separated from the infralabials by a row of smaller plates. Ear- 

 opening large, with an anterior denticulation of five or six long, narrow 

 scales. Side of neck between ear-opening and fore limb with numerous 

 folds, covered with granular scales. A strong antehumeral, but no com- 

 plete gular, fold. A well-developed median dorsal crest begins half the 

 length of the interparietal behind this plate, and runs continuously to and 

 along the tail, being highest on the proximal fourth of the tail. The 

 dorsal regions of the neck, body, and tail are covered with rather small, 

 keeled, mucronate scales, which, on the body, change gradually to smaller, 

 keeled, mucronate laterals. These again change gradually into the 

 smooth ventrals, which are a little smaller than the dorsals. The gular 

 scales are smooth, smaller posteriorly, smallest below the ears. The scales 

 on the chest are largest, smooth and imbricate. The limbs are provided 

 above with keeled, and below with smooth, scales. The posterior surface 

 of the thigh is covered with keeled, imbricate scales. The lateral caudals 

 are strongly keeled and mucronate ; while the inferior caudals are smooth 

 proximally, but become keeled on the distal portion of the tail. 



The color above is olive brown, unicolor on the top and sides of the 

 head, but relieved with dark brown or black spots or cross-bars on the 

 body, limbs, and base of tail. The lower surfaces are greenish white. 

 The gular region is suffused with dark gray, and the throat and chest 

 bear discrete, rounded spots of blackish brown. 



Length to anus mm. 65 



Length of tail 120 



Snout to ear 15 



Width of head 13 



Fore limb 34 



Hind limb 54 



Base of fifth to end of fourth toe 21 



Height of crest on nape 1 



Height of crest on midbody .8 



Height of crest on tail 1.2 



Variation. — The lizards of Charles, Champion, Enderby, 

 and Gardner-near-Charles islands seem to differ in no respect. 

 The sexes agree in coloration, except that the males have 

 darker throats and larger dorsal spots. Females may have 

 either white or grayish throats, spotted with black. The inter- 



September 17, 1913 



