LIZARDS. 71 



types into a creature of an essentially forbidding and threatening aspect. The 

 membranous frill, previously applied closely to the neck, is suddenly, and syn- 

 chronously with the opening of the mouth to its fullest width, erected in such 

 manner that it stands out at right angles around the animal's head. The dimen- 

 sions of this frill in adult individuals may be as much as from eight to ten inches in 

 diameter and in its erected condition the lizard's body, when facing the observer, 

 is almost, if not entirely, concealed from view. A fairly correct presentment of the 

 Frilled Lizard thus aroused to anger or standing defiantly at bay is embodied in the 

 two photographs from life reproduced as the heading to this Chapter. The ferocious 

 appearance of Chlamydosaurus here depicted only in monochrome is materially 

 enhanced in the living subject by the glowing tints of vermilion red, yellow, and 

 steel blue that suffuse that portion of the frill which covers the front of the neck 

 and chest, combined with the bright yellow distinctive of the tongue and the lining 

 membrane of the mouth and throat. The dashes and pencillings of rosy red which 

 accentuate the outlines of the upper and lower jaws and the margin of the singular 

 ciliated irides, also add sensibly to the creature's angry aspect. 



With the assistance of the talented natural history artist, Mr. F. W. Frohawk, 

 the author has succeeded in obtaining a highly characteristic portrait of the example 

 which he recently brought alive to England, with which has been incorporated the 

 colours, copied from life, of one of the brighter male examples immediately after 

 its capture in Roebuck Bay. This portrait appeared originally as a black and white 

 drawing in the pages of the "Field" for August 3rd, 1895, and subsequently with the 

 colours, as added by the author, in conjunction with a paper descriptive of the animal 

 contributed to the " Proceedings of the Zoological Society " for the same year. The 

 author's obligations to the " Field " Newspaper and the Council of the Zoological 

 Society for permission to reproduce the illustration in these pages may be here most 

 appropriately recorded. 



With regard to the significance and utility of the erectile frill in Chlamydosaurus, 

 the fact that this organ is of insignificant proportions in young examples, and attains 

 its full development only in adult individuals, would appear to indicate that, as a 

 structure, it has been developed within comparatively recent times and does not 

 represent the residual heritage of a remote ancestry. Respecting its function, there 

 can be but little doubt that it fulfils simply the rdle of a " scare-organ," where- 

 with it terrifies, and diverts the projected attack of, many ordinary enemies. 

 Instances have, in fact, been related to the author of dogs which will readily rush 



