352 The Descent of Man. Past II 



female bronze-coloured. 57 No doubt the colours of some snakes 

 are protective, as shewn by the green tints of tree-snakes, and 

 the various mottled shades of the species which live in sandy 

 places ; but it is doubtful whether the colours of many kinds, 

 for instance of the common English snake and viper, serve to 

 conceal them; and this is still more doubtful with the many 

 foreign species which are coloured with extreme elegance. The 

 colours of certain species are very different in the adult and 

 young states. 58 



During the breeding-season the anal scent-glands of snakes are 

 in active function ; 59 and so it is with the same glands in lizards, 

 and as we have seen with the submaxillary glands of crocodiles. 

 As the males of most animals search for the females, these 

 odoriferous glands probably serve to excite or charm the female, 

 rather than to guide her to the spot where the male may be 

 found. Male snakes, though appearing so sluggish, are amorous ; 

 for many have been observed crowding round the same female, 

 and even round her dead body. They are not known to 

 fight together from rivalry. Their intellectual powers are 

 higher than might have been anticijDated. In the Zoological 

 Gardens they soon learn not to strike at the iron bar with which 

 their cages are cleaned ; and Dr. Keen of Philadelphia informs 

 me that some snakes which he kept, learned after four or five 

 times to avoid a noose, with which they were at first easily 

 caught. An excellent observer in Ceylon, Mr. E. Layard, saw 60 

 a cobra thrust its head through a narrow hole and swallow a 

 toad. " With this encumbrance he could not withdraw him- 

 " self; finding this, he reluctantly disgorged the precious mor- 

 " sel, which began to move off; this was too much for snake 

 " philosophy to bear, and the toad was again seized, and again 

 ■ l was the snake, after violent efforts to escape, compelled to part 

 " with its prey. This time, however, a lesson had been learnt, 

 " and the toad was seized by one leg, withdrawn, and then 

 " swallowed in triumph." 



The keeper in the Zoological Gardens is positive that certain 

 snakes, for instance Crotalus and Python, distinguish him from 

 all other persons. Cobras kept together in the same cage 

 apparently feel some attachment towards each other. 61 



57 Dr. A. Gunther, 'Reptiles of brates,' vol. i. 1866. p 615. 

 British India,' Ray Soc. 1864, pp. 60 ' Rambles in Ceyh n.' in 'Annala 

 304, 308. and Mag. of Nat. Hist.' 2nd series, 



58 Dr. Stoliczka, * Journal oi vol. ix. 1852, p. 333. 



Asiatic Soc. of Bengal,' -vol. xxxix. 61 Dr. Gunther, 'Reptiles cf 



1870, pp. 205, 211. British India,' 1864, p. 340. 



" y Owen, ' Aiatcmy of Yerte- 



