LIZARDS. 75 



was presented by the writer, in August, 1895, to the Zoological Gardens in the Regent's 

 Park, where, for several weeks, its phenomenal aspect and habits proved to be a 

 source of much attraction. 



The gait of the Frilled Lizard when running erect is remarkable for the 

 widely-extended and highly-elevated positions which the hind-limbs successively assume. 

 This is shown with marked distinctness in the photographs reproduced in Plate XII. 

 As also indicated in these figures, the pendent fore-limbs during bipedal progression 

 would seem to be subservient to the function of balancing the body, being, as illustrated 

 more particularly by Fig. 5, extended synchronously with the elevation of the opposite 

 hind-limb. Interest of a special kind is attached to the bipedal perambulation of 

 Chlamydosaurus on account of the fact that, while apparently unique among all the 

 existing representatives of its class, such a method of deportment was typical of the 

 long-extinct Eeptilian group of the Dinosauria. That such huge representatives of that 

 tribe as the colossal Iguanodons of which a restored skeleton in the Natural History 

 Museum measures no less than thirty feet in length skipped along the ground in the 

 jaunty style of the species now under notice is scarcely to be imagined, but it may, 

 at the same time, be inferred that with many of the smaller members of the Dinosaurian 

 class this mode of progression was largely approximated. On the other hand, it 

 might, of course, be argued that the Frilled Lizard's mode of progress has been evolved 

 at a comparatively -recent date with reference only to its special environments. As 

 indicated on a previous page, the species is essentially arboreal in its habits, abiding 

 for the most part on the trunks and lower limbs of the trees in the tropical scrubs. 

 It was observed repeatedly by the author of the examples he had in confinement that, 

 when liberated in a room or elsewhere, they invariably made towards and ascended, 

 as far as possible, any vertical object, such as a table leg, or even that of an onlooker. 

 In accomplishing this manoeuvre their vertical perambulatory deportment necessarily 

 placed them at the greatest advantage. It is noteworthy, however, in this direction 

 that, while certain of the Australian Lizards belonging to the genus Varanus are 

 equally or even more essentially tree climbers, their perambulation is exclusively 

 quadripedal. 



This question of the analogy of the gait of Chlamydosaurus to that of certain 

 of the Dinosauria, together with a discussion as to the possible zoological affinities 

 of this remarkable living lizard with members of that extinct group, is entered 

 into at some length in two articles contributed by the author to the " Proceedings of 

 the Zoological Society " for November, 1895, and " Nature," of February 27, 1896, 



