Chameleons.] 



MUSEUM OF ANIMATED NATURE. 



83 



Fish, floating carrion, pigs, dogs, and other ani- 

 mals surprised on the banks of the river, are the 

 food of the crocodile ; yet on land escape is by no 

 means difficult, as the legs are ill-formed lor running, 

 and the little false ribs, or appendages to the ver- 

 tebrae of the neck, limiting the lateral motion of 

 that part, render sudden turns a matter of difficulty. 

 In the water, on the contrary, the animal is prompt 

 and rapid ; lashing his tail from side to side, he 

 cleaves the waters like an arrow, leaving a track 

 behind him from the impetuosity of his progress. 

 Sometimes it is said he will dart forward into the 

 middle of the river, uttering a loud bellowing, his 

 eyes glaring and his body swollen, while with his 

 powerful tail he lashes the surrounding water, till it 

 is worked into a loam. This exhibition of excite- 

 ment ended, he darts off to his accustomed covert, 

 and regains his concealment. 



The eggs of the crocodile are of an oblong shape, 

 hard, and somewhat larger than those of a goose ; 

 and the young, compared with their' gigantic pa- 

 rents, are very small, but display, even at that early 

 period their innate ferocity. Numbers, both of 

 young and eggs, are destroyed by beasts and birds 

 of prey. The Ichneumon (described in vol. i., p. 

 214, Fig. 951) has been from an ancient date cele- 

 brated for the havoc it makes among them. 



Though none of the crocodile tribe are natives of 

 Europe, Malte Brun, in his ' Syst. Geol.,' vol. viii., 

 p. 193, states that a crocodile is still preserved at 

 Lyons, which was taken about two centuries ago in 

 the Rhone, but no particulars are given. We can 

 only account for the circumstance by supposing the 

 animal to have wandered along the coasts of the 

 Mediterranean from the Delta of the Nile, or per- 

 haps from some of the rivers of North-western Africa, 

 and have made its way into the Mediterranean. 



2134.— The Gavial 

 (Gavialis Gangeticus). Head of Gavial of the 

 Ganges. Gangetic Crocodile. Crocodilus tenuiros- 

 tris, Daudin ; Or. longirostris, Schn. 



The Gavial, of which only one species is known, 

 is subject to considerable variations in its progress 

 from youth to maturity. It is characterized by the 

 jaws being very much elongated and narrow, and 

 somewhat depressed beak, armed with formidable 

 teeth to the number of one hundred and eighteen or 

 one hundred and twenty. The first and fourth tooth 

 on each side of the lower jaw are the longest, and 

 are received not into cavities of the upper jaw, but 

 into conspicuous notches. This long and formid- 

 able beak sinks suddenly from the forehead, and is 

 expanded at its extremity, where the valvular nos- 

 tril form a large oval cartilaginous mass. The eye- 

 lid contains in its substance the rudiment of a 

 bony plate. 



At Fig. 2134 are represented, a, the Skull of the 

 Great Gavial, seen from above ; b, the lower jaw ; 

 c, the profile of the Skull ; d, an outline of the Head 

 of the Gavial, covered with the integuments. There 

 are musk glands under the lower jaw. The hind 

 feet of the Gavial closely resemble those of the true 

 crocodiles, but the cervical plates are arranged more 

 nearly like those of the caiman ; forming a long 

 band, commencing on the nape of the neck, and 

 prolonging themselves to the dorsal plates. There 

 IS, however, some diversity, as seen at Fig. 2135, 

 representing the cervical plates of two individuals, 

 from Cuvier. The scales of the flanks are oval and 

 flat, the keels of the plates, forming the dorsal 

 cuirass, are low, but the crest of the tail is much 

 elevated. 



The Gavial is a native of the Ganges, and is the 

 largest of the living Sauria, often exceeding twenty- 

 five feet in length ; it is one of the scourges of the 

 river, and is very formidable from its strength and 

 ferocity. The dying Hindoo exposed upon the 

 bank, or the dead body consigned to the sacred 

 waters, often becomes the prey of this dreaded mon- 

 ster. 



Several species of fossil crocodile have been dis- 

 covered ; they belong to a distinct genera, and it is 

 remarkable that those examples alone, which have 

 elongated beaks, approximating to the modern 

 Gavial, occur in formations anterior to and including 

 the chalk, whilst those with a short broad snout, 

 like that of the caiman, appear for the first time in 

 tertiary strata, containing in abundance the remains 

 of Mammalia. " The discovery of crocodilean 

 forms," says Dr. Buckland, " so nearly allied to the 

 living Gavial, in the same early strata that contain 

 the first traces of the Ichthyosaurus and Plesiosau- 

 rus, is a fact which seems wholly at variance with 

 every theory that would derive the race of crocodiles 

 from Ichthyosauri and Plesiosauri, by any process of 

 gradual transmutation or development. The Hrst 

 appearance of all these three families of reptiles, 

 seems to have been nearly simultaneous ; and they 

 all continued to exist together until the termination 

 of the secondary formations, when the Ichthyo- 

 sauri and Plesiosauri became extinct, and forms of 

 crocodiles approaching the cavman and alligator 

 Vol. II. 



were for the first time introduced." (' Bridgewater 

 Treatise,' vol. i., p. 254.) 



Of the long-beaked fossil forms, that which ap- 

 proaches the nearest to the living Gavial is the Ste- 

 neosaurus, of which Fig. 2136 represents the muzzle, 

 from a specimen procured at Havre ; according to 

 Dr. Buckland, the relics of the same species are 

 met with in the Kimmeridge clay of Shotover Hill, 

 near Oxford. In another fossil genus, viz., Teleo- 

 saurus, the beak is also narrow and elongated, but 

 the nasal orifice, instead of opening upwards, ter- 

 minates the anterior apex of the upper jaw, as seen 

 at Fig. 2137. Referring to Fig. 2138, a represents 

 the head of Teleosaurus Chapmanni, seen from 

 above ; h, the head of another individual of the same 

 species, seen from below, showing the lower jaw ; c, 

 an inside view of the extremity of the lower jaw. 

 This species is found in the lias, in the neighbour- 

 hood of Whitby, and in the great oolite of Oxon. 



In Crocodilus Spenceri (Fig. 2139), the skull ap- 

 proaches closely to that of the caimans, and is broad 

 with a short and heavy snout. It is found in the 

 London clay of the Isle of Sheppey. 

 • We shall here leave the crocodiles, the family 

 Crccodilidae of some authors, the order Emydosauri 

 of De Blainville, Mr. Gray, and others, and advance 

 to the true Sauria, which appear to emerge gra- 

 dually through a series of forms to the Ophidia 

 (or Snakes), or at least to approximate towards 

 them. Of the various systematic arrangements of 

 the true Sauria, none appear to us so clear and 

 simple as the one given by that eminent naturalist 

 Mr. Gray, in the ' Synopsis of the Contents of the 

 British Museum' (1840). But at the same time wc 

 must not omit an express notice of the admirable 

 ' Erp6tologie G6n6rale,' of MM. Dum6ril and 

 Bibron, one of the standard works on reptiles of 

 the present day, to which we shall often have 

 occasion to refer. 



Before we enter upon our subject, however, it may 

 be as well to allude to an old superstition, which, 

 under various phases, has passed from the pages of 

 Pliny, Dioscorides, Solinus, .S)lian. and others, to 

 those of the naturalists of the last century. Who 

 has not heard of the basilisk or cockatrice, the king 

 of serpents, with a regal crown upon its head, 

 blighting the herbage with its breath, and striking 

 dead with a glance of its eye ? 



It would appear that several sorts of these crea- 

 tures, "bodied forth" by imagination, were sup- 

 posed to exist, all " monstra horrenda ;" and one, 

 the concentration of evil, was said to be produced 

 from the eggs of extremely old cocks, hatched under 

 toads and serpents. This parentage, indeed, is 

 attributed by some to the whole brood. Pliny, after 

 stating that this creature kills with a glance of the 

 eye, adds that "the Cyreriaic Province produces 

 him, of the size of not more than twelve fingers, 

 and remarkable for a white spot like a diadem on 

 his head. He drives away all serpents by hissing ; 

 nor does he impel his body like the rest by a mul- 

 tiplied flexion, but advances lofty and elevated. 

 He kills the shrubs not only by contact, but by 

 breathing on them, scorches up the green herbage, 

 and splits the rocks, such power of evil is there in 

 him. It was formerly believed that if killed by a 

 spear from on horseback, the virulence of the poi- 

 son, conducted through the weapon, destroyed not 

 only the rider but the horse also." 



Johnston, who enters very gravely into all the evil 

 qualities of this basilisk, doubts the possibility of its 

 asserted mode of production, but he and others of 

 our earlier writers believed in its existence. " Yet 

 was the basilisk mortal, and had foes proof against 

 its fatal glance and withering breath. Of these one 

 was the weasel ; this animal feared not the en- 

 counter, and when bitten or hurt in the combat, it 

 would retire, and eat some rue, the only herb which 

 the monster's breath could not dry up, and again 

 return to the charge, and never cease the conflict 

 till it had stretched its enemy dead." Another 

 dreaded animal was a cock, for though sprung from 

 the egg of such a bird, mirabile dictu,no sooner did 

 it hear " the cock's shrill clarion," than it instantly 

 expired. We present our readers with two represen- 

 tations of basilisks or cockatrices, from Aldrovandus, 

 one of which he owes to Grevinus. Fig. 2140, 

 Basiliscus in SoUtudine Africae vivens ; the basilisk 

 inhabiting the deserts of Africa. Fig. 2141, Basilis- 

 cus, sive Regulus, Grevini. The basilisk, or kinglet, 

 of Grevinus. 



We have said enough about a fable utterly un- 

 worthy of our serious notice. The title basilisk, or 

 basiliscus, is applied by modern naturalists to a 

 genus peculiar to South America. 



Family CHAM/ELEONID.E (CHAMELEONS). 

 These singular reptiles, which are distributed to 

 Africa, India and its islands, the Seychelles Islands, 

 Bourbon, and Mauritius, Australia, &c., but not 

 America, as far as is at present ascertained, may be 

 distinguished by the deep compressed form of the 

 body, surmounted by an acute dorsal ridge ; by the 



toes, which are united together as far as the latt 

 joint, and armed with sharp claws, being disposed 

 in two sets, antagonizing with each other, three 

 being placed anteriorly, two posteriorly, and form- 

 ing, like the foot of the parrot, efficient graspers ; by 

 the surface of the skin being covered, not by scales, 

 but by minute horny granules ; and by the pre- 

 hensile power of the tapering tail. The head, we 

 may add, is large, and from the shortness of the 

 neck, seems as if set upon the shoulders ; it is some- 

 what wedge-shaped in figure, being broad across 

 the occiput, which is surmounted with an elevated 

 crest or casque, in some species g^reatly developed ; 

 an abrupt ridge overtops both eyes, extending 

 thence to the muzzle, where each ridge meets. The 

 mouth is very wide, and the jaws are armed with small 

 trilobed teeth. The tongue is a most extrordinary 

 organ, and is the instrument by means of which the 

 animal takes its insect prey. It consists of a hollow 

 tube, with a fleshy tuberculated " apex, and is 

 capable of being darted out instantaneously to a 

 great distance, and as instantaneously retracted. 

 When retracted it folds up within itself, somewhat 

 after the manner of a pocket telescope ; it is lubri- 

 cated by a glutinous saliva, and when fully ex- 

 tended is vermiform in appearance. So rapidly does 

 the animal launch this instrument at a fly, or other 

 insect, or at a drop of water on a leaf or twig, and 

 so rapidly is it withdrawn, that the eye can but just 

 follow the movement. 



The eyes of the chameleon have a singular and odd 

 expression. They appear mere points : the whole of 

 the anterior portion of the ball, excepting the pupil, 

 being covered with skin, forming a single circular 

 eyelid. The balls thus covered with skin, to which 

 they are attached, are set each in a large orbit, 

 with a deep furrow around them, and roll about, 

 perfectly independent of each other ; so that the 

 axis of one eye may be directed backwards, for- 

 wards, upwards, or downwards, and that of the other 

 in a contrary direction, the animal making two dis- 

 tinct surveys at the same moment, thus producing a 

 grotesque effect. 



We have heard of the chameleon's food being the 

 air ; it lives, however, on more substantial diet ; but 

 this story may have arisen from the following cir- 

 cumstance : — the lungs are exceedingly voluminous, 

 and these the creature is able to flll with air, so as 

 to puff itself up, and in this state it often remains 

 for hours without any movement of respiration being 

 perceptible ; on exhausting the lungs of the air, the 

 sides of the body fall in, and the frame has a meagre 

 appearance till the lungs are again inflated, when it 

 becomes suddenly bloated as before. Certain con- 

 tinuations of these lungs penetrate the numerous 

 cellules into which the abdominal cavity is regularly 

 divided, while others penetrate under the skin be- 

 tween the muscles, to which the former adheres only 

 by lax membranes, especially on the spine, down the 

 centre of the under parts, and on the limbs and tail. 

 It may be asked, — Are not the changes in the 

 colour of the skin, for which the chameleon has been 

 long celebrated, dependent in some degree on the 

 respiration and differences of condition in the 

 lungs ? Barrow indeed declares, that previously to 

 the chameleon's changing colour, it makes a long 

 inspiration, swelling out twice its usual size, and 

 that as the inflation subsides the change of colour 

 gradually takes place, the only permanent marks 

 being two small dark lines passing along the sides. 

 From this account some have ascribed the transi- 

 tions of tint to the influence of oxygen on the fluids 

 and tissues of the body ; and there is much appear- 

 ance of probability in the theory. 



Dr. Weissenborn attributes these changes to the 

 varied influence of light on the nervous system. 



The following is M. Milne Edwards's theory, which 

 after all does not leave the subject completely ex- 

 plained. See ' Ann. des Sciences Nat.,' Jan., 1834. 

 The results of his observations are : — 



1. "That the change in the colour of chameleons 

 does not depend essentially either on the more or 

 less considerable swelling of their bodies, or the 

 changes which might hence result to the condition 

 of their blood or circulation ; nor does it depend on 

 the greater or less distance which may exist between 

 the several cutaneous tubercles ; although it is not 

 to be denied that these circumstances probably 

 exercise some influence upon the phenomenon. 



2. " That there exist in the skin of these animals 

 two layers of membraneous pigment, placed the one 

 above the other, but disposed in such a way as to 

 appear simultaneously under the cuticle, and some- 

 times in such a manner that the one fnay hide the 

 other. 



3. " That everything remarkable in the changes of 

 colour which manifest themselves in the chameleon 

 may be explained by the appearance of the pigment 

 of the deeper layer to an extent more or less consi- 

 derable, in the midst of the pigment of the super- 

 ficial layer ; or from its disappearance beneath this 

 layer. 



4. "That these displacements of the deeper pig- 



M2 



