Chap. XII. 



Reptiles. 



357 



Chamceleon Owenii (fig. 36), from the West Coast of Africa, the 

 male bears on his snout and forehead three curious horns, of 

 which the female has not a trace. These horns consist of an 

 excrescence of bone covered with a smooth sheath, forming part of 

 the general integu- 

 ments of the body, 

 so that they are 

 identical in struc- 

 ture with those of a 

 bull, goat, or other 

 sheath - horned ru- 

 minant. Although 

 the three horns 

 differ so much in 

 appearance from 

 the two great pro- 

 longations of the 

 skull in G. bifurcus, 

 we can hardly doubt 

 that they serve the 

 same general pur- 

 pose in the economy 

 of these two ani- 

 mals. The first con- 

 jecture, which will occur to every one, is that they are used 

 by the males for fighting together; and as these animals are 

 very quarrelsome, 69 this is probably a correct view. Mr. T. W. 

 Wood also informs me that he once watched two individuals of 

 0. pumilus, fighting violently on the branch of a tree ; they flung 

 their heads about and tried to bite each other ; they then rested 

 for a time, and afterwards continued their battle. 



With many lizards, the sexes differ slightly in colour, the 

 tints and stripes of the males being brighter and more distinctly 

 defined, than in the females. This, for instance, is the case with 

 the above Cophotis and with the Acnnthodactylus caper, sis of 

 S. Africa. In a Cordylus of the latter country, the male is 

 either much redder or greener than the Temale. In the Indian 

 Calotcs nigrilabris there is a still greater difference ; the lips also 

 of the male are black, whilst those of the female are green. In 

 our common little viviparous lizard (Zootocn vivipura) "the 

 " under side of the body and base of the tail in the male are 

 f bright orange, spotted with black ; in the female these parts 

 " are pale-greyish-green without spots." 70 We have seen that 



69 Dr. Bucholz, * Monatsbericht 70 Bell, « History of British 



K. Preuss. Akad.' Jan. 1874, p. 78. Reptiles,' 2nd edit. 1849, p. 40. 



Fig 36. Chameleon Owenii. Upper figure, male 

 lower figure, female. 



