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but also from time to time in lapping, as it were, a glittering drop of water from any pendant leaf or spray. Its entire action presents, in its almost unexampled rapidity, a singular and striking contrast to all the other movements of the animal, which are peculiarly sluggish and inert.

The habits of the chameleon are entirely insectivorous, and its disposition is otherwise mild and inoffensive. This, at least, is the character assigned to it, by eyewitnesses, in modern times; although it differs considerably from that given in an old work by Edward Topsel, entitled a History of Four-footed Beasts and Serpents, compiled chiefly from the writings of Conrad Gesner, and published in 1658. Being desirous to have our own favourable impressions of the creature's character confirmed, by older writers of more experience than ourselves, we turned to the volume in question, and found as follows: A chameleon is a fraudulent, ravening, and gluttonous beast, impure, and unclean by the law of God, and forbidden to be eaten; in his own nature wild, yet counterfeiting meeknesse when he is in the custody of man.'-(P. 676.) It seems, however, that if his life is worse than worthless, he may be turned to essential service after death. If a chameleon be sod in an earthen pot, and consumed 'till the water be as thick as oyl, then, after such seething, take 'the bones out, and put them in a place where the sun never 'cometh; then, if ye see a man in the fit of the falling-sicknesse, ' turn him upon his belly, and anoint his back from the os sacrum 'to the ridge-bone, and it will presently deliver him from the fit ; ⚫ but after seven times using, it will perfectly cure him.'

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The etymology of the term chameleon has occupied the attention of several learned Thebans.' The ancient Greek writers bestowed upon it the name of auarksoy, which simply signifies low or humble lion'; and the meaning of the word is much more clear than the reason of its application; for we know of no creature which less resembles any lion, either high or low. It may be that the crested or rugose character of the head, suggested to some one, in early times, an idea associated with the shaggy front of the king of the forest. Isidorus indeed prefers tracing it to two Greek substantives, χαμηλος and λέωνcamel-lion, as it were, by reason of the curvature of the spine, the length of the legs, and the conical form of the tail.' But this does not seem to simplify the subject, and the fact of the Latin writers naming it chamaleo, favours the former significa tion. However, its real character is sufficiently curious, independent of any nominal ambiguities.

The most noted peculiarity of this reptile is undoubtedly its change of colour, and the exposition of this feature in its physi


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ology has exercised both the ingenuity and the imagination of many observers. "The general or usual colour in the chameleon,' says Dr Shaw, so far as I have been able to ascertain, from my own observation of such as have been brought into this country in a living state, is from a bluish-ash colour (its natural tinge) to a green and sometimes yellowish colour, spotted unequally "with red. If the animal be exposed to a full sunshine, the un'illuminated side generally appears, within the space of some minutes, of a pale yellow, with large rounded patches or spots ' of red-brown. On reversing the situation of the animal, the same change takes place in an opposite direction, the side which was before in the shade now becoming either brown or ash colour, while the other side becomes yellow and red; but these changes are subject to much variety, both as to intensity of colours and disposition of spots.'* MM. Dumeril and Bibron confirm this statement as to the variable position of the spots Les taches régulières des flancs en particulier ne se produisent pas constamment sur les mêmes points de la peau, quoique les dessins se répètent assez souvent chez le même in'dividu; mais ils ne correspondent pas tout-à-fait à des endroits * semblables, comme on s'en est assuré par des indications ou des repères laissés dans ce but sur la peau de l'animal.' † Dr Spittal never observed the change of colour to depend in any degree upon the hue of the substance on or near which the animal was placed. The usual colours of his specimens during the day were various shades of green, in the form of irregular spots and stripes. When seen by candle-light, the tint seemed of a yellower hue, spotted with brown, the spots becoming paler as the light was removed to a distance. Dr Neill's specimen, kept near Edinburgh, was generally greenish during the day, and of a dingy cream-colour in the night.

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Although manifested in a stronger degree by chameleons than by any other known creatures, a change of colour is by no means peculiar to this genus; it being distinctly observable in several other Saurian groups, such as Draco and Anolis, as well as among frogs and toads, and even in many fishes. The change is gradual and transitionary, rather than marked or sudden. Authors of all ages have differed regarding its causes, whether remote or immediate. It has certainly nothing to do with the colour of objects placed in juxtaposition, as Pliny maintains;

General Zoology. Vol. iii. p. 256.

† Erpétologie Générale. T. iii. p. 171.

Edinburgh New Philosophical Journal. Vol. vi. p. 292.

nor with the reflection of the sun's rays, as Solinus supposes; but bears a more complex relationship to various circumstances such as the intensity of light to which the individual is exposed, and the state of its feelings in respect to tranquillity or disquietude. The direct or more immediate cause, however, physiologically considered, seems to be the action of the lungs (which are large, dilatable, and prolonged) upon the circulating system; and the phenomenon itself is always most remarkable among those reptiles in which, the general cutaneous covering not adhering closely or uniformly to the muscular layer beneath, a large portion of air is distributed below the skin. There is therefore much truth in the view maintained by Aristotle, and some other ancient authors, that this change of colour occurs only when the animal is in a state of inflation. En effet,' says Cuvier, leur poumon les rend plus ou moins transparents, contraint plus ou moins le sang à refluer vers la peau, colore même ce fluide plus ou moins "vivement, selon qu'il se remplit ou se vide d'air.'* According to Mr Houston, the skin is not only very thin, but highly vascular; and he thinks that the colour of the blood appearing through that semi-transparent covering, and variously modified by its more permanent hues, is of itself sufficient to account for every diversity of tint which the chameleon can assume. He maintains the opinion that these effects are produced by vascular turgescence, just as the increased redness in blushing is caused by a rush of blood to the cheeks.'

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Olaus Wormius (Museum,' 1655) seems to have been among the first to maintain that the alteration of colour was regulated by internal feelings; and Kircher (1678) supports a corresponding theory of emotion and volition. The majority of modern authors, however, seek to explain the fact in question somewhat variously, by the modifying action of a peculiar respiratory system,-by that action in union with the state of the pulmonary circulation,-or by the variable functions of the different layers of which the pigmentum is presumed to be composed. It may be that the very multiplicity of these explanations ought to be regarded as a proof that something is yet wanting to complete our knowledge of the subject. We agree, however, with Mr Houston, that the proximate cause is closely connected with the circulating system.

In connexion with the preceding portion of our enquiries, we must briefly advert to the extraordinary construction of the organs of respiration in these animals. The lungs are double,

* Règne Animal. T. ii. p. 59.

symmetrically formed, and, when empty, present the appearance of two small fleshy masses beneath the heart; but, when filled with air, they become so inflated as to cover the whole intestines, and even exceed in size the ordinary dimensions of the entire cavity of the abdomen. The pulmonary cells in general are very large, but their mass is lobate, or divided on either side into seven or eight appendages, with pointed terminations. Of these slender portions, which are themselves excessively prolonged, some penetrate the numerous cells which as it were divide the abdomen into regular compartments, thus forming reservoirs of air; while others stretch between the muscles and beneath the skin, which is itself so free as to envelope the body rather in a loose sack than in the fixed form of a cutaneous covering. Thus the lungs in the chameleon may be regarded as proportionally larger and more prolonged than those of any other vertebrated animal. But besides this unexampled extension, a singular supplementary organ was long ago discovered by Vallisnieri. This is a loose membranous sack or vesicule, somewhat in the form of a goitre, which is placed in a cavity beneath the base of the hyoid bone, and is capable of being filled with air, or emptied, at the creature's pleasure. It may be likened to the air-vessel of fishes, just as the glottis and trachea greatly resemble those of birds. It is in these remarkable peculiarities, according to MM. Dumeril and Bibron, that we ought to seek the explanation of several of the most singular circumstances in the life and actions of the chameleon, such as its power of continuing for many hours in an inflated state, during which not the slightest respiratory movement is perceptible, the frequent changes in the form and bulk of body to which it is subject, as well as the rapid motion of the tongue, and even the superficial change of colour.

Zoologists are by no means well instructed regarding the general habits of the chameleon in the natural state; at least, we are not ourselves aware that much additional knowledge has been gained regarding them since the days of Cestoni-an apothecary of Leghorn, who corresponded largely on these subjects with Vallisnieri; as we find in the works of the latter, published in 1696. The sexes do not habitually consort together, but seek each other's society only for a brief period. The female deposits about thirty eggs in a hole of a few inches deep, which she excavates in the earth with her hind-feet.* She then covers them with the loose

* Servendosi,' says the Italian author, 'a questo lavoro delle sole 'zampe di dietro,'-an expression strangely and most inaccurately trans

earth, and an additional coating of slender twigs and leaves. The eggs are of a rounded form, and greyish white in colour. Their shell is calcareous, and of a porous texture, which admits the influence of the atmospheric air during the development of the included young.

We shall terminate our account of the chameleon by a note in illustration of the geographical distribution of the genus.* There are no less than fourteen different kinds. Africa may be said to be their characteristic country; as it appears from an analysis of the subjoined note, that naturalists know of none which is not found in some quarter of that continent, or in one or other of the great adjacent islands, although three of the species likewise occur elsewhere. Of those last alluded to as not being exclusively African, one is found in Spain and the East Indies, another in Georgia, and a third in New Holland, and other southern lands. The Spanish species is said by M. Bory de St Vincent to be not uncommon around the Bay of Cadiz, and is sometimes seen in dwelling-houses suspended from the ceiling as an object

lated by the authors of the Erpétologie Générale, en se servant un'iquement de la patte anterieure droite,'- -as if the creature, instead of using both her hind-legs, had recourse merely to the right fore-paw.

*1. Chamæleo vulgaris or Africanus. This is the earliest described, and best known species. It occurs all along the southern shores of the Mediterranean from Egypt to the Straits, and is the only species found in Europe. It is not uncommon in the southern parts of Spain, but has not been observed in South Africa, nor in Senegal, or other western regions. The inaccurate Seba represents it under the euphonious name of Chamæleo Mexicanus seu cuapapalcatl. We need scarcely observe that none of the genus has ever been found in the New World. A peculiar variety, though not a distinct kind, occurs in India. 2. C. verrucosus. Madagascar. 3. C. Tigris. Seychelle Islands. 4. C. nasutus. This, the smallest of the species, occurs in Madagascar. 5. C. pumilus. Cape of Good Hope, and Seychelle Islands. 6. C. lateralis. Madagascar and the Mauritius. 7. C. Senegalensis. From Senegal. This species is represented by Shaw under the name of common chameleon. His figure seems copied from a plate in Miller's Cymelia Physica. 8. C. dilepis. The distribution of this species must be very extensive, if, as is alleged, the specimens sent to Paris from Tiflis, are identical in kind with those captured by Mr Bowdich on the coast of Guinea. 9. C. cucullatus. Madagascar. 10. C. tricornis. Island of Fernando Po. 11. C. pardalis ; and 12, C. Parsonii. Madagascar and the Isle of France. bifidus. Of this species the geographical distribution is singularly extensive, It is said to occur in the Moluccas, the Isles of Sunda, Bourbon, Continental India, and New Holland. 14. C. Brookesi, Mada


13. C.

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