February 27, 1896] 



NATURE 



\97 



their fore-limbs and long tails elevated clear of the 

 ground. 



The attempt was made on the spot to permanently 

 register, with the aid of the Kodak camera, the absurdly 

 grotesque appearances these lizards presented when 

 progressing in this bipedal fashion. Such, however, was 

 the speed at which the animals ran, that the shutter of 

 that instrument did not work fast enough to secure any- 

 thing better than a blur at close quarters, and it was only 

 by bringing an Anschutz camera with its most rapid 

 roller-blind shutter to bear on the specimen, after its 

 arrival in London, that the Figs. 2 and 3, here repro- 

 duced, were secured. While even these partake much of 

 the nature of silhouettes, they will serve to indicate the 

 more characteristic running attitudes which this lizard 

 may assume. 



Fig. 2 in this series carries with it so essentially human 

 an aspect that one is sorely tempted, at the risk even of 

 mcurring scientific contumely, to place a cricket-bat in 

 its right hand. The distance Chlamydosaurus will traverse 

 in this remarkable erect position may average as much 



sauria, and among whose representatives a bipedal locol 

 motive formula was apparently a characteristic feature. 

 A reference, however, to the skeleton of Chlamydosaurus 

 does not encourage any sanguine anticipations that may 

 have been previously entertained in this direction. It 

 yields no indication of that peculiar avian modification 

 of the pelvic elements, adapted for bipedal locomotion, 

 that are so essentially diagnostic of the more typical 

 Dinosauria, while in all general points it is indistinguish- 

 able from that of the ordinary Agamidte. 



Though, as a consequence, no serious attempt would 

 be justified to correlate the erectly progressional Chlamy- 

 dosaurus with such ponderous specialised Dinosaurs as, 

 say, Iguanodon or Brontosaurus^ there are some few 

 species at the lacertilian end of the chain, that probably 

 presented when living, a by no means remote likeness to 

 this existing type in both aspect and gait. The Comp- 

 sognathus longipes of A. Wagner, from the lithographic 

 stones of Solenhofen, is more especially worthy of 

 mention in this connection. In size, some three feet 

 long only, and in the proportions of the limbs and other 

 points, it must have been almost a counterpart of Chlamy- 

 dosaurus kingi. It is particularly noteworthy of it, more- 

 over, that, as pointed out by the late Prof Huxley 



2. — Chlamydosaurus running erect. Posteru 

 Anschutz hand camera. 



view, taken with 



a^ thirty or forty feet at a stretch, and when, after resting 

 momentarily on its haunches, it will resume its running 

 course. When, however, a short space of a few yards 

 only have to be covered, the animal runs on all-fours, 

 sitting somewhat high on its haunches after the manner 

 of many ordinary lizards, such as the Grammitophora, 

 previously referred to. 



The profile outhne of Chlamydosaurus^ presented by 

 Fig. 3, is peculiarly interesting, since it possesses so much 

 in common with that of a running long-tailed bird, such 

 as a pheasant. This bird-like aspect of the frilled lizard, 

 as exhibited when it crosses the observer's path in bipedal 

 fashion, has been the recent subject of remark to me by 

 a friend familiar with the species in the Kimberley dis- 

 trict of Western Australia. 



Special interest is attachable to this avian-like ambu- 

 latory deportment of Chlamydosaurus by reason of the 

 generally accepted interpretation that the birds are 

 modified descendants of a reptilian archetype. The 

 temptation is naturally also very great to institute com- 

 parisons between, and to suggest possible affinities with, 

 this peculiar lizard and the extinct group of the Dino- 



NO. 1374. VOL. 53] 



Fig. 3. — Chlamydosaurus running erect. Profile view. 



(" Anatomy of Vertebrata," p. 262, ed. 1871), the pelvic 

 elements of Compsognathus correspond more essentially 

 with those of the ordinary lizards than with those of the 

 aviform Dinosauria, the pubes in particular being ap- 

 parently directed forwards and downwards, like those of 

 lizards. This type, as likewise Sfenopelyx, is also referred 

 to by the same authority (p. 263) as indicating that the 

 more typical modification of the pelvis, and in which the 

 pubes are directed backwards parallel with the ischia, as 

 in birds and Iguanodon, "was by no means universal" 

 among the Dinosauria or Ornithoscelida, as Prof Huxley 

 preferentially named them. 



Notwithstanding the distinctly recognised lacertilian 

 character of the pelvis of Compsognathus, Prof Huxley 

 had no hesitation in assigning to this type an erect 

 bipedal method of locomotion. Writing of it in the 

 Popular Science Review, 1866, that illustrious biologist 

 remarks : " It is impossible to look at the conformation 

 of this strange reptile, and to doubt that it hopped or 

 walked in an erect or semi-erect position after the manner 

 of a bird, to which its long neck, slight head, and small 

 anterior limbs must have given it an extraordinary 

 resemblance." 



The silhouette presentment of Chlamydosaurus afforded 

 by Fig. 3, forms a not inapt embodiment of the flesh-clad 



