REPTILES. 25 



It constitutes one of the numerous interesting novelties obtained by Mr. 

 Darwin in the Galapagos. The specimens, which are of various ages, were taken 

 in Chatham Island and in Charles Island. 



Genus— CENTRURA. Bell. 



Caput breve, triangulare. Aures magncB, antich cutis plica, haud dentutd, partim 

 celatcs. Nares magnce, rotundce. Gula transversa suhplicata. CoUum atque 

 corpus haud cristata ; hoc depressum, latum, cute longitudinaliter plicatd. Cauda 

 teres, basin versus subdepressa, squamis Jortibus spinosis verticillatis . Squamae 

 capitis numerosce, parvcB, rotundatce, non imbricatce. — corporis minimcE, rotundce, 

 subconvexcB, Iceves. Fori femorales et prae-anales nulli. Dentes palatini. 



The propinquity of this genus both to Oplura and to Doryphorus is very 

 obvious. It differs, however, from both in several structural characters. From 

 the former in the absence of denticulations on the anterior margin of the ear, and 

 of a nuchal crest ; from the latter in the presence of palatine teeth. Its place is 

 probably between these two genera. 



Centrura Flagellifer. Mihi. 

 Plate XIII.— Fig. 2. 



Description. — Head almost cquilaterally triangular, the muzzle rounded; scales of the head small, 

 nearly equal, rounded, not imbricated, those of the temples subconical ; nostrils round, large, 

 confined to the nasal scales. Ears rather large, the tympanum lying beneath the surface, and 

 partly concealed by an anterior fold of skin, which is not denticulated, as in Oplura. Skin of 

 the neck folded at the sides, that of the body flaccid, and with strongly marked lateral folds, 

 extending from the shoulder to the thigh. Scales of the neck and back very small, round, 

 shghtly convex, very smooth. Skin of the throat rugose, with a transverse pectoral fold not 

 very strongly marked. Scales of the throat similar to those of the back ; those of the belly 

 broader and less convex ; all perfectly smooth. Tail about the length of the head and body 

 flattened at the base, then round, surrounded with strong spinous verticillated scales, of which 

 there are about fifty circles ; beneath smooth. Legs of moderate length, strong, covered with 

 small conical, imbricated scales. The toes compressed towards the extremity, and terminated 

 with a strong, short, compressed nail. 



Colour. — The colour can only be partially described, as the specimen has been long in spirits. It 



E 



