REPTILES. 401 



when this snake is excited these scales are rubbed against 

 each other, which produces "a curious prolonged, almost 

 hissing sound." * With respect to the rattling of the 

 rattlesnake, we have at last some definite information; for 

 Prof essor Aughey states, f that on two occassons, being him- 

 self unseen, he watched from a little distance a rattlesnake 

 coiled up with head erect, which continued to rattle at 

 short intervals for half an hour; and at last he saw another 

 snake approach, and when they met they paired. Hence 

 he is satisfied that one of the uses of the rattle is to bring 

 the sexes together. Unfortunately he did not ascertain 

 whether it was the male or the female which remained 

 stationary and called for the other. But it by no means 

 follows from the above fact that the rattle may not be of 

 use to these snakes in other ways, as a warning to animals 

 which would otherwise attack them. Nor can I quite dis- 

 believe the several accounts which have appeared of their 

 thus paralyzing their prey with fear. Some other snakes 

 also make a distinct noise by rapidly vibrating their tails 

 against the surrounding stalks of plants ; and I have 

 myself heard this in the case of a Trigonocephalus in South 

 America. 



Lacertilia. The males of some, probably of many kinds 

 of lizards, fight together from rivalry. Thus the arboreal 

 Anolis cristatellus of South America is extremely pugna- 

 cious: " During the spring and early part of the summer, 

 two adult males rarely meet without a contest. On first 

 seeing one another, they nod their heads up and down 

 three or four times, and at the same time expanding the 

 frill or pouch beneath the throat; their eyes glisten with 

 rage, and after waving their tails from side to side for a 

 few seconds, as if to gather energy, they dart at each other 

 furiously, rolling over and over, and holding firmly with 

 their teeth. The conflict generally ends in one of the com- 

 batants losing his tail, which is often devoured by the 

 victor. " The male of this species is considerably larger 

 than the female ;J and this, as far as Dr. G anther has been 



*Dr. Anderson, "Proc. Zoolog. Soc.," 1871, p. 196. 

 f " The American Naturalist," 1873, p. 85. 



\ Mr. N. L. Austen kept these animals alive for a considerable 

 time; see " Land and Water," July, 1867, p. 9. 



