LIZARDS. we 
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, reproduced in these pages, 
forms a not inapt embodiment of the flesh-clad skeleton that must have suggested 
itself, ghost-like, to the learned Professor's mind. And it is among the author’s 
keenest personal regrets that, through the recent decease of Prof. Huxley, he should 
have been deprived by so short an interval of gladdening his former teacher’s eyes 
with the sight of a living organism which, if only in the direction of superficial 
analogy, so nearly realised one, among the many, of his most sagacious inter- 
pretations of the fossil past. 
A remaining point in the erect running gait of Chlamydosaurus invites brief 
attention. Such is the construction of the hind foot and its component digits that, when 
thus running, the three central digits only rest upon the ground. As a consequence 
of this structural peculiarity, the track made by this lizard when passing erect over 
damp sand or other impressible soil, would be tridactyle like that of a bird, and 
would also correspond with the tracks that are left in Mesozoic strata by various 
typical Dinosauria. This tridigitigrade formula of the gradation of Chlamydosaurus, 
induced by the great relative shortness of the first and fifth digits, is distinctly 
indicated in fig. 1 of the Plate previously referred to. 
Whether or not the bipedal locomotive comportment of Chlamydosaurus has 
been transmitted by heredity from a lizard-like Dinosaurian such as Compsognathus, 
or has been re-developed independently among its allocated family group of the 
Agamide, is a question concerning which it would be unbecoming temerity on the 
writer's part to pronounce a verdict. The phenomenon, while dominant among the 
Reptilia of bygone ages, is, with the exceptional instance afforded by Chlamydosaurus, 
apparently extinct among living types, and is, on that account alone, of unique 
interest. 
