396 



NA TURE 



[February 27, 1896 



Zoological Society's Gardens, where it was on view for 

 some weeks, has afforded many fellow-naturalists the 

 opportunity of verifying the phenomena here recorded. 



The most conspicuous structural feature of Chlarny- 

 dosaurus kingi is the extraordinary development of the 

 cuticle of the neck, that gives to it its popular title. 

 This takes the form of a voluminous frill or collar, which, 

 while the animal is at rest or undisturbed, is neatly folded 

 in symmetrical pleats around the creature's neck and 

 shoulders. No sooner, however, is the lizard excited to 

 hostility by the approach of a threatening assailant, than, 

 coincident with the opening of the mouth, the frill is sud- 

 denly erected, much after the manner of the unfurling of 

 an umbrella, and stands out at right angles to the longer 

 axis of the body, measuring under such conditions some 

 seven or eight inches in diameter. 



The mechanism by which the erection and depression 

 of the frill of Chlauiydosaurus is accomplished is 

 intimately connected with a slender process of the hyoid 

 bone, which traverses the substance of the frill on each 

 side, and is so adjusted that the opening of the creature's 

 mouth and the erection of the frill are synchronous 

 operations. A characteristic photograph from life, of this 

 lizard in a condition of excitement, and standing at bay, 

 with mouth open and frill erect, is afforded by Fig. i. 



them long in a state of captivity. The several specimens 

 in my possession became fairly accustomed to dieting on 

 raw meat, though they would not take to this artificially 

 substituted pabulum voluntarily. On the slightest excite- 

 ment, however, they would open their mouths and erect 

 their frills, and on which occasions it was a simple matter 

 to administer pieces of meat, which were then readily 

 assimilated. 



The most remarkable feature placed en evidence by the 

 specimens I kept in captivity, was their peculiar method 

 of perambulation. The statement that the frilled lizard 

 was in the habit of running erect on its hind legs only, 

 was made to me in Queensland some years ago. I failed, 

 however, to verify this assertion through the single living 

 specimen I there had in captivity for a short interval ; 

 and neither was a friend in the northern district of the 

 colony more fortunate, who, at my request, made experi- 

 ments with several specimens. I was, on these grounds, 

 inclined to suspect that the rumour, that had previously 

 reached me, was the outcome of an optical illusion ; many 

 lizards, such as Graviinitophorcc^ running so erect on their 

 haunches that it might be imagined their fore-limbs were 

 raised from the ground.^ 



It was consequently to my no small gratification and 

 I delight, on becoming the owner of several specimens, in- 



FiG. I. — Chlamydosaiirus Kingi, standing at bay with erected frill. (Reproduced from an instantanous photograph 



byW. Saville-Kent.) 



representing one of many I was fortunate in securing 

 from the specimen I brought to England. 



The function of the frill in Chlamydosaurus is, as 

 apparently indicated by the circumstances and conditions 

 under which alone it is displayed to view, purely that of a 

 ■" scare-organ," wherewith by its sudden expansion many 

 of its would-be assailants are frightened and deterred from 

 attacking it. Instances have, in fact, been recorded to me 

 of dogs, which will readily rush upon and kill other and 

 larger lizards, such as Varani, refusing to come to close 

 quarters with so formidable-looking an object as Chlamy- 

 dosaurus, when it turns upon them with gaping mouth 

 and suddenly erected frill. 



Chlamydosaurus displays, however, additional de- 

 fensive tactics. When approached these lizards will often 

 spring aggressively at the intruder, and in addition to 

 using their not very formidable teeth, will lash sideways 

 with their long rough tails with such vigour as to smartly 

 sting the hand which may fall within range of the un- 

 expected impact. 



The natural food of the frilled lizard consists almost 

 exclusively of Coleoptera and other bark-frequenting 

 insects ; a fact which emphasises the difficulty of keeping 



NO. 1374, VOL. 53] 



eluding the one brought to England, obtained for me with 

 the assistance of the aborigines of Roebuck Bay, Western 

 Australia, that I found myself in a position to fully estab- 

 lish the truth of the report concerning the erect gait of 

 Chlamydosaurus that had been comnmnicated to me in 

 Queensland. Possibly the specimens previously experi- 

 mented with had been slightly injured during capture, 

 and lacked the stamina to walk upright. At all events 

 the Roebuck Bay examples, brought in straight from the 

 bush, were in vigorous health, and at the first trial when 

 left at liberty, save for a light retaining cord, ran 

 along the ground almost perfectly erect, with both 



1 It has quite recently come to my knowledge that a report of the bi- 

 pedal comportment oi Chlamydosaurus was communicated some years since 

 to Dr. Henry Woodward, F.R.S., who referred to the circumstance in a 

 paper on " Forms Intermediate between Birds and Reptiles" in the Quart. 

 Journ. Geological Society, vol. xxx. 1874; The concluding paragraph of 

 that paper, wherein Dr. Woodward favours the interpretation that " the 

 bipedal habit of the secondary reptiles is a peculiarity still maintained by 

 the Australian Chlamydosaurus," is of special interest with relation to the 

 latter portion of this article. The assertion made by Dr. Woodward's in- 

 formant in the journal quoted, that Chlaviydosaurus is common near 

 Sydney, is a mistake due, probably, to the circumstance that another lizard, 

 Amphibolurus barbatus, having a less developed neck-membrane, inhabits 

 that district, and is sometimes also known locally as the Frilled Lizard. 

 The structure of this type, however, would not permit of its bipedal pro- 

 gression. 



