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CHAMA 



CHAMELEON 



and soon acquired a great reputation as a skilful 

 and witty delineator of the humorous side of 

 Parisian life. In 1843 began his famous connection 

 with the Charivari, in which paper and in the 

 Journal des P6lerinages Ire continued to delight 

 his fellow-citizens until close upon his death on 

 6th September 1879. He was profoundly sceptical, 

 but not unkindly, and obtained, as Edmond About 

 pointed out, the success of an homme d 1 esprit. His 

 masterpieces were chiefly social rather than politi- 

 cal, and among his skits may be mentioned Proud- 

 homana, Bagneurs et Buveurs d'Eau, Souvenirs de 

 Garrison, and L 'Exposition de Londres. Several 

 good collections of his comic illustrations have been 

 made for instance, Douze Annees Coiniques ( 1880), 

 with an introduction by L. Halevy, and Les 

 Folies Parisiennes (1883), with an introduction by 

 Gerome. In Sala's Paris herself again ( 1882) are a 

 good many specimens of Cham's art. 



4 li;im;i. a genus of bivalve molluscs, the only 

 surviving type of a family which was once ex- 

 tremely numerous and abundant, especially in the 

 Jurassic and Chalk times. The genus is represented 

 by about half a hundred living forms, restricted to 

 warmer waters, and especially common about coral 

 reefs. The general appearance is somewhat clam- 

 like, the valves are unequal, of considerable thick- 

 ness, and covered with leaf or scale-like outgrowths. 

 They are very passive animals, usually fixed, with 

 the mantle margins fused together, with very small 

 foot and respiratory apertures, with well-developed 

 hinge and an external ligament, and often or a 

 bright colour. Some forty fossil species are 

 known from Cretaceous and Tertiary strata, and 

 the genus is of interest as the sole survivor of a 

 once much larger family. The common English 

 name for shells of this genus is Clam (q.v. ). 



Chamseleon (Gr. chamaileon, 'ground lion'), 

 a large genus of lizards, forming a very distinct 

 family. Among the most distinctive features may 

 be noted the soft tuberculated skin, with its power 

 of changing colour ; the coiled tail, adapted for 

 curling round the branches of trees ; the division 

 of the toes of fore and hind feet into two bundles ; 

 the absence of an external ear-drum or tympanic 

 membrane ; the long worm-like insect-catching 

 tongue, capable of extremely rapid protrusion. 

 Even more remarkably distinctive, however, are 

 certain peculiarities in the skeleton, and especially 

 in the skull, which separate the chamaeleons from 

 all other lizards. 



Description. The body is flattened, and bears a 

 toothed crest of skin along the back. The head is 



Chamseleon. 



triangular, surmounted by a ridge. The animal 

 stands unusually high upon its legs. The fore-feet 

 are divided into three united internal digits and 

 two external ; the reverse ( and the digits, corre- 

 sponding to our great and second toes, form one 

 bundle, and the other three external another 



united group) occurs in the hind-feet. The digits 

 are tipped by long^ sharp claws. The long com- 

 pressed tail is curled ventralwards. The mouth- 

 aperture is small, but the tongue extremely long. 

 It is the most active part of the animal, is cup- 

 shaped at the end, covered with a viscid secre- 

 tion, and very efficient in insect-catching. The 

 large lateral eyes, with circular lids leaving only a 

 small aperture, are very active, and can be rapidly 

 turned in all directions, a possibility which to some 

 extent compensates for the stiffness of the head. 

 The skin is soft, loose, and shagreen-like, the scales 

 being very small. The glandular pores common 

 on the thighs and near the anus of lizards are 

 absent. 



Among the internal peculiarities may be noted 

 the largeness of the lungs, which admit of being 

 greatly distended, so as to puff out the body 

 into marked plumpness. They appear to be con- 

 nected with surrounding air-spaces. The habit 

 the chamaeleon has of thus blowing itself out, 

 taken along with its power of fasting, gave origin 

 to the ancient supposition that it fed on air. The 

 skeletal peculiarities are numerous. The chamse- 

 leons differ from all lizards except the Amphis- 

 bcena (q.v.), in having no ' columella ' or epiptery 

 goid skull-bone, and no interorbital septum, and 

 from all other forms in the fact that the pterygoid 

 and quadrate bones are not united. The latter is 

 firmly fused to the skull, and the parietals are also 

 peculiar in their firm attachments. The teeth are 

 confined to a ridge along the summit of the jaws. 

 The vertebne are hollow in front ; the breastbone 

 is small, and only a few anterior ribs reach it ; as 

 in the geckos, many of the posterior ribs are united 

 ventrafiy by hoops across the abdomen ; there 

 are no clavicles ; the scapula and coracoid of the 

 shoulder-girdle and the ilia of the hip-girdle are 

 peculiarly long and narrow. 



Life and Habit. Except as regards tongue and 

 eyes, the chamseleons are very sluggish. They are 

 strictly arboreal lizards, moving very slowly, in 

 perfect silence, and waiting rather than hunting 

 for their insect prey. At a distance of several 

 inches, about half as long as the body in some 

 cases, they can most unerringly catch the uncon- 

 scious insect. Probably the most familiar fact 

 about chamseleons is their power of changing 

 colour. Under the thin outer skin there are two 

 layers of pigment-containing cells, the outer bright 

 yellow, the inner brown to black. Under nerve 

 control the disposition and expansion of the pig- 

 ment-containing cells vary, and this produces 

 change of colour. The change depends much more 

 on internal emotions, expressing themselves in 

 nervous stimulus and inhibition, than on external 

 physical influences. The change appears to be 

 rather emotional than protective. Most chamse- 

 leons are oviparous, and lay 30 to 40 thin -shelled 

 eggs, which are deposited in an excavated hollow 

 and covered over with earth and leaves. Moseley 

 has described a South African species which brings 

 forth its young alive. 



Species and Distribution. The genus Chamseleo 

 is a large one, and some naturalists split it up. 

 Chamseleons are especially at home in the Ethiopian 

 region, but may occur beyond its limits. The com- 

 monest of the numerous species is C. vulgaris, 

 which is abundant in Africa, and is also found 

 in South Europe (Andalusia). The predominant 

 colour varies in different species. Many males 

 are adorned with horns on tne head. One form, 

 distinguished as a distinct genus ( Rhampholeon ), 

 has a tail too short for clasping purposes, but this 

 loss is made up for by accessory structures on the 

 feet. The chamseleon was well described by 

 Aristotle, but in later days became the subject of 

 numerous ridiculous fables. It was also in repute 



