286 THE ZOOLOGIST. 



perceive it ; they are as inquisitive and fond of novelties as 

 monkeys. 



The changes which go on in a reptile's economy are so slow 

 and involve so low a degree of oxygenation, that it demands very 

 little " fresh air." Such dimensions for the snakes' abode as we 

 have given are called for to permit of their taking adequate 

 exercise, not by respiratory necessities. People often exclaim, 

 " Why, they won't be able to breathe ! " when they see a cage 

 closely covered in cold weather, not heeding that the inmates 

 have relatively quite as much air as we enjoy in a room with the 

 door and window shut and the chimney stopped up, and certainly 

 ignorant of the fact that the amount of oxygen in the cage would 

 be sufficient for its inhabitants for perhaps a couple of years 

 without renewal : witness the length of time they will exist in a 

 stoppered bottle. Abundant ventilation, then, is a matter to be 

 desired rather for the comfort of the owner, in insuring a pure 

 atmosphere within the cage whenever he opens it, than to be 

 looked upon as an essential for the health of the serpents them- 

 selves. When it can be obtained without sacrifice of warmth, it 

 should, of course, be so ordered ; but it is better to check or 

 altogether dispense with a current of air if it entails cold. 

 Every opportunity of airing the interior when the snakes are 

 absent should be seized, and after it has been scrubbed they 

 ought not to be replaced until every part of it is dry, nor should 

 the gravel be spread over a wet floor. The utmost cleanliness 

 must be observed, soiled portions of the gravel removed daily, 

 and the water never allowed to grow foul, otherwise the cage 

 becomes offensive and the snakes very unpleasant to handle. 

 Drainage must be attended to also. The tray of earth and 

 charcoal in the small heated cage is a great deodorizer ; where 

 this is not employed, a fine wire basket, filled with coarse pieces 

 of charcoal, placed in some convenient situation, will absorb any 

 bad odour. Some serpents are much more pronounced than 

 others in this respect. The Common Grass-snake has already 

 been noticed, and it is curious that many species closely allied to 

 it have the same peculiarity, the Indian River-snake (Tropido- 

 notus quincunciatus) for instance. Most species, when only 

 recently taken and alarmed, have a disagreeable smell, but they 

 soon lose this as they become accustomed to their position. 

 The Rattlesnake has a foetor, under some circumstances, which is 



