August II, 1881] 



NA TV RE 



337 



the Island of Socotra. There are also the occipital flaps in 

 C. Peit-rsti' (48), from Eastern Africa. The two remain- 

 ing chameleons are so distinct from the foregoing that 

 they rank as a distinct genus called Rhampholeon, a 

 genus which was instituted by Dr. Gunther in 1S74. The 

 first of these, R. spectrum - (49) is from the Camaroons ; 

 the second, A'. Kcrstenii'^ (50) is from Eastern Africa. 

 Both agree and remarkably differ from all other chame- 

 leons in having the tail short, it being only one-third the 

 total length, or even less. Though its end is prehensile, 

 its prehensile action mu;t be much less perfect than that 

 of the tails of the preceding forty-eight kinds ; but this 

 defect is compensated for by the development of a sharp 

 tooth, or denticle, at the inner side of the base of each 

 claw, which must give it a firmer grip. Moreover in R. 

 spectrum, though not in R. Kerstenii, the grip is yet 

 further aided by a spine which projects vertically from 

 the inner, or fle.-ior, surface of each finger or toe. In R. 

 spectrum each eyebrow is produced into a flexible horn- 

 like prominence. In R. Kerstenii two long processes 

 project forwards, one over and in front of either eye. 



Thus the geographical distribution of the chamasleons 

 is very remirkable. With the single exception of the 

 common species they are entirely confined to Africa and 

 certain more or less adjacent islands, and exist mainly on 

 the south of the equator. No less than twenty-one out of 

 the fifty Idnds are from Madagascar, and of the twenty- 

 five kinds which have been enumerated as having horns 

 or other remarkable processes on the head, no less than 

 seventeen are from the same very interesting inland, 

 which is thus the great home of chamx-leons generally, 

 and especially of these curiously distinguished kinds. The 

 plate-snouted (C aniimena and C. Labordi), the bony, 

 double-horned species I'C. minor, C. bijurcus, C. Parsonii, 

 and C. O' Shatighncssii), and the lofty-helmeted (C. 

 cafyptrattis and C. catcaratns) kinds are quite peculiar to 

 Madagascar. Those with occipital lobes are found not 

 only there, but also in Mozambique and the Island of 

 Socotr.i. The Madagascar single-homed C, rhinocerattis 

 is. rese nbled by the East African C. XlcUeri and the 

 flexible-?nouted Madagascar form, c". gallits, is resembled 

 by the East .African C. nasutiis. The species with true 

 horny sheaths to their horns (C. inontium and C. 0'<ijcnii) 

 are exclusively West African forms. 



Fernando Po possesses three species. Two are from 

 the Camaroons. One is an inhabitant of the Seychelle 

 Islands, and two are from the Comoro Islands between 

 .Africa and Madagascar. Apart from the common species 

 three kinds are from Eastern Africa, two from Egypt 

 and Abyssinia, nine froin Western Africa, and eight from 

 Southern Africa. 



Such are the leading facts with respect to chama:leons 

 considered by themselves. Let us now consider their 

 more significant relations to other animals. 



The entire mass of animals of all kinds, from what is 

 commonly called the animal kingdom, in contrast with 

 and in distinction fro:n the vegetable kingdom : this 

 great whole is divided into certain vast groups callel 

 sub-kingdom>, and the highest of them, called the verte- 

 brate sub-kingdom (because its members possess a spinal 

 column), comprises ourselves, with all beasts, birds, rep- 

 tiles, efts, frogs and toads, and fishes. We and beasts 

 constitute what is called a chss — the c\3.%s 3/amiiialin. 

 Birds form another cKi^s — Az'es. Reptiles (i.e. all 

 tortoises, lizards, serpents, and crocodiles, with certain 

 extinct kinds) together constitute the class Reptilia. The 

 efts of all kinds, with all frogs and toads, and some other 

 creatures, living and extinct, form the class Batrachia, 

 while all fishes are grouped together in the one class 

 Pisces. But these five classes are not equally distinct 

 one from another. Birds and reptiles, batrachians and 



' P. Z. S., 1864, p. 470. » P Z. S., 1S74, p. 443, PI. LVII. 



3 Peters in von der Decken's *' Reisen," iii. p 12, Table I. Fig i ; see 

 also Ann. and Mag. oj Nat. Hist., September, 1880, p. 238. 



fishes go together as two sets of classes or provinces. 

 On the provmce containing birls and reptiles the name 

 Saiiropsiita has been bestowed, while the term Ichthyo- 

 psida has been used to denote the province which contains 

 both B.itrachians and Fishes. 



The existmg class of repriles contains four orders : — 

 (i) CrocodHia (crocodiles and alligators) ; (2) Lacertilia 

 (lizarJs) ; (3) Opindia (serpents) ; and (4) Chelonia 

 (tortoises and turtles). 



The order Lacertilia is m.ade up of a certain number of 

 large groups, each of which is called a family, which 

 family is again composed of genera, while each genus 

 consists of one, tivo, few or many species. 



The chama:leons, as we have seen, form fifty species 

 arranged in two genera : forty-eight species in the genus 

 Chamaleo, and two in the genus Ramptiolecn. These 

 two yencra together constitute a famil) — a family of the 

 order Lacertilia. 



Putting aside on this occasion a certain very excep- 

 tional genus called Hatteria, ihe families of the order 

 Lacertilia may be enunienitcd as follows : — the true 

 lizards (Lacertida) ; the S incs (Scincida) ; the Chal- 

 cidians [Chatcidct) ; the Iguanians (It^uanidce') ; the 

 Geckos {Gcchotidce) : and the Monitors {I'aranidce). 



From all these families th it of the chama;leon differs 

 most widely. It differs from all of these: — (i) in the 

 compressed body raised from the ground by its long 

 limbs ; (2) in its tongue ; (3) in its eyes ; (4) in the 

 shape of its feet ; anf (5) by the form of the tail. It 

 further differs from the Iguanians, Lacertians, Seines, and 

 Chalcidians, in that its body is not covered with scales. 



There are certain Iguanians which present a slight 

 resemblance to the chamoeleons : such are the American 

 Polychrtis, and still more Splicerops, vihich has the eye 

 covered with a granular eyelid with only a small central 

 aperture, and has an equal facility in changing colour. 

 These, however, are but superficial agreements, and in 

 all essential points Splicerops is a true Iguanian, and in no 

 way a chameleon. 



Prof Parker assures us that while the chameleon is 

 an animal, the structure of the skull of which is "spe- 

 cialised to the utmost," it is nevertheless in other respects 

 a very low form. 



The answer to our question, "What is a chamasleon?" 

 is, then, that it is a very exceptional family of the order 

 Lacertilia, an order of the class Reptilian, a class which, 

 together with birds, f.imi the .Sauropsidi.in province of the 

 great vertebrate sub-kingdom of animals. 



Can wc gain any light as to the mode of origin of 

 chamasleons .■' 



The best light we can obtain as to the origin of existing 

 forms is derived from the fossil remains of creatures 

 nearly allied to them. In this way we have been able 

 pretty clearly to ascertain that hog-like creatures and 

 ruminating animals are diverging offshoots from a much 

 more ancient, common, and intermediate type. 



In this way also we have, I think, fair evidence to show 

 that the oats are derived from creatures more or less nearly 

 allied to the existing civets. 



But the science of organic fossil remains— paleontology 

 — has only as yet been able (so far as I am aware) to 

 point to one relic which has been supposed to be of cha- 

 meleon nature — part of a lower jaw from Eocene deposits 

 in North America. It would be curious if an ancient 

 chameleon should be discovered to have inhabited a 

 region so distant from the home of the existing kinds as 

 is North America. It would not however be an unparal- 

 lelled fact, for the existing C Id World camel was once a 

 New World form. The true nature however of the frag- 

 menti.ry fossil is very doubtful, and we may therefore say 

 that a, yet we have no evidence as to the antiquity of the 

 family. Hut should the fossil turn out to be really part of 

 the jaw of a chameleon, it would but tend to show that 

 the group itself existed already in Eocene times ; it won 



