NO. 1151. A NEW SPINY-TAILED IGUANA— STEJNEaER. 383 



Remarls. — There is another specimen (No. 22704, U.S.N.M.) of same 

 age and sex, which (litters in no essential feature from the one described, 

 except that the dorsal crest consists of 36 spines only, and that the inter- 

 ruption between the dorsal and caudal crests is complete, being not even 

 indicated by a row of carinated scales. Another peculiarity is that one 

 of the small scales at the base in front of each dorsal spine has devel- 

 oped into a very minute spine. A third specimen (No. 24459, U.S.N.M.) 

 is very young, only 198 mm. (7.8 inches) long. The dewlap is already well 

 indicated, being 5 mm. (0.2 inch) deep; all the other diagnostic charac- 

 ters are also present and well marked. The dorsal crest is quite pro- 

 nounced, the spines being triangular, about as high as long; the large 

 ones are standing some distance apart, the intervals being wider than 

 the basis of the spines; the small ones at the anterior and posterior 

 ends are placed quite close; the number of the spines is 37; the crest 

 perfectly interrupted on the rump. Eight femoral pores. Color essen- 

 tially as the adults. 



The present species is not nearly related to any of the species known 

 hitherto, and does not require special comparison with any of them. It 

 comes, perhaps, nearest to C. quinquecarinata (Gray), but the structure 

 of the tail is very different, and the dorsal crest of G. palearis is both 

 longer and higher, with much fewer and broader spines. In addition it 

 differs from G. quinrpiecarinata, as well as from all the other species of 

 the genus, in the possession of the enormously developed dewlap. That 

 part of the generic definition of Gtenosaura which reads "no gular 

 pouch" will consequently have to be changed, as the presence of this 

 appendage will not justify the estabhshment of a separate genus for 

 G. palearis. 



