468 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiii. 



differentiation of the enlarged upper tibial scales and in the soutella- 

 tion of the tail. In C. hA'erl only the fourth to eighth caudal whorls 

 are composed of two scale rings, the others of three, ^'iz, the posterior 

 spinous one and two smaller basal rings, while in ( '. palearis there is 

 only one yery small basal ring throughout. In the latter the median 

 spine of this basal ring is also correspondingly small, so that the median 

 caudal crest consists of alternate large and small spines, while in C. 

 hal-erl the spines of the crest are equal or nearly so. Moreoyer, in 

 this species the lateral spines are much less deyeloped, being, in fact, 

 smaller than the median series, while the opposite is true of C. palearis. 

 There are many more structural differences. n()tal)ly the smaller size 

 of the head scales of ( '. Jxihr!^ but the charactei-s pointed out aboye 

 are sufficient to separate the two species. The coloration is also some- 

 what different, inasmuch as the lateral black bands, though in the 

 specimens of < '. halet'l before me rather obscure, neyertheless involye 

 the dorsal crest, the spines of which at the crossing of the band are 

 jet black, while in C. palearis the crest appears to be uniform pale. 



The dewlap of ("1 hakerl is not quite as large as in (\ palearis. The 

 former species, therefore, in this, as in the scutellation of the tail, tills 

 somewhat the gap between ( '. palearis and the other species of the 

 geiuis, thus demonstrating the wisdom of not creating a new generic 

 term based upon that character. 



