THE IGUANOID LIZARDS 2491 



as perfect health as its companion. The lizard was evidently unused to the wiles 

 of the British spider. ' ' 



The crested anolis {A. cuvieri), belonging to a small group with compressed 

 and crested bodies and tails, is remarkable for the great extent to which the pouch 

 on the throat can be inflated, probably for the purpose of terrifying foes. 



Two lizards, respectively from Jamaica and Columbia, differ from 

 :ra all the species of true anolis in having prehensile tails, in consequence 

 of which they are referred to a distinct genus Xiphocercus. In a third genus, 

 Chamcelolis, the cheek teeth have smooth and nearly spherical crowns. 



The strange form of the members of the present genus of iguanoids 

 probably suggested to the earlier naturalists the imposition of the 

 name basilisk, a term which, as all our readers are doubtless aware, originally 

 denoted a fabulous snake-like reptile before whose deadly glance every living being 

 save the cock perished. Be this as it may, the reptiles now known as basilisks are 

 large, although perfectly harmless members of the present family, belonging to a 

 group distinguished from the preceding one by the absence of dilatation of the toes, and 

 the more or less marked backward prolongation of the hinder portion of the head. In 

 the presence of a large crest on the upper surface of the tail, the basilisks recall the 

 sail-tailed lizards in the agamoid group, of which, indeed, they may be regarded as 

 the representatives in the present family. As a genus they are characterized by 

 the head in the adult males being produced backward into a large cartilaginous 

 lobe; by the compressed form of the body and tail, which are covered with small 

 overlapping scales, and by the presence of a crest on the back and tail in the males, 

 such crests being always supported on the back by the prolonged spines of the ver- 

 tebrae, and frequently also in the tail. Although there is a transverse fold on the 

 throat, the pouch characterizing the anolis lizards is wanting. The long limbs are 

 covered with keeled scales, and the outer sides of the hind-toes have a much 

 developed lobe of skin. The cheek teeth have three-cu.sped crowns, and teeth are 

 borne on the pterygoid bones. Internally, the basilisks form an exception to the 

 members of this and the two preceding families in that the inner extremities of the 

 collar bones have a loop-like expansion, as in the geckoes; while they differ from 

 the anolis lizards in the absence of the false abdominal ribs so frequently present in 

 this and the preceding families. 



The basilisks are represented by four species from tropical America, among 

 which the figured helmeted basilisk (Basiliscus americanus) is the one most com- 

 monly known. It is the largest representative of the genus, attaining a length of 

 about thirty-one inches, of which nearly three-quarters is taken up by the tail; and 

 is one of two species characterized by the great height of the crest of the tail in the 

 males, which is supported by prolongations of the spines of the vertebras. Inhabit- 

 ing Panama and Costa Rica, it is specially characterized by the undivided head 

 crest of the males; the scales on the under surface of the body are smooth. The 

 natural color of the creature is probably green, although specimens preserved in 

 spirit are olive brown above, and dirty white beneath. The back is marked with 

 more or less distinct blackish transverse bands, while a lightish streak runs from 

 the temple to the neck, and a more defined one from the region of the eye to the 



