BRITISH EEPTILES 



81 



Details may be found in books which deal expressly with the subject.* 

 The animal lover who has ingenuity and time at his disposal 



can do much to add to our knowledge by devising and carrying out 



experiments as to the capabilities of his pets. Their powers of sight, 



their sense of smell, can be accurately compared and noted. The 



sensitiveness of their skin to light, their colour changes, and even 



such simple matters as the way in which they climb, offer many 



opportunities for useful observations. 



Although adult adders will scarcely, if ever, take food in captivity, 



and hence cannot be kept 



indefinitely, it is not hard 



to procure females in July 



and August containing 



eggs in an advanced stage 



of development from which 



the young will shortly be 



hatched. On their appear- 

 ance the mother snake can 



be removed, and although 



the young have never as 



yet been induced to feed, 



it is possible that their 



right food has not been 



given to them. At any 



rate, the more experiments that are made in this direction, the 



better ; and ultimate success, should it come, would amply repay 



the trouble taken. 



* Such as, " The Vivarium," by Rev. G. C, Bateman, Upcott Gill, price 7s. 6d. The 

 enthusiast in this direction may well make himself familiar with the work of F. Werner, 

 Biol. Centralb., XXIII (1902), pp. 737-758, 



F 



From a photograph by Douglas English, B.A. 



FIGURE 91. A Smooth Snake (Coronella). 



