9510 Reptiles. 



not this advantage, but then its jaws open widely and the skin stretches 

 to the very verge of bursting, thus giving it the power of completely 

 enclosing and easily swallowing its victim ; whereas the Corouella, if 

 it could not enfold its prey, would be unable to hold it when seized, 

 or eflfectually to resist its struggles. Should it be said that the viper 

 has the same structure of the skull with the Corouella, and yet never 

 crushes its prey, it must be remembered that, before deglutition, it 

 invariably inflicts a fatal wound by means of its poison-gland ; it can 

 therefore afford to wait quietly until the venom has done its work, 

 without the necessity of holding its victim either in its jaws or in the 

 folds of its body. 



As I observed just now, the Corouella bathes frequently and for long 

 periods after each meal, either swimming on the surface or lying im- 

 mersed. In either case it takes great care not to dip its head, ex- 

 cepting in very warm weather, and then, if the water be fresh, I have 

 known the animal sink its head beneath the surface and retain it there 

 for a quarter of an hour at a time, its cheeks all the while puffing out 

 and again collapsing, like the gills of a fish. To ascertain whether 

 this curious fact has anything to do with the act of drinking, I dis- 

 sected one of my specimens immediately after it had taken a bath : 

 however, a very insignificant amount of water flowed from the 

 stomach and intestinal canal. That so small a quantity should be 

 contained in the stomach I attribute to the absence of a broad tongue 

 and the stiffness of the jaws. Lenz never succeeded in observing this 

 fact, and had great doubts, in consequence, whether ophidians drink 

 at all — an opinion which has been transferred to other works on the 

 subject, that of Schinz, for instance. 



The winter sleep of Corouella auslriaca is neither so deep nor so 

 long as that of many animals to which it is nearly allied. In both the 

 seasons of 1857 and 1858 (neither of which, however, was very severe) 

 I kept all my specimens of Corouella, Tropidonotus and Anguis in 

 simple glass boxes, the bottoms of which were strewed with sand and 

 sawdust. Not one of the Coronellas was in the least affected by the 

 cold until it reached a mean of '20° (Reaumur), where it remained for 

 several days ; and they woke up immediately on being transferred to 

 a moderately warm room ; whereas the blindworms and lizards still 

 continued in a torpid condition. Nor did the Coronellas, like their 

 companions, bury themselves in the sand, but invariably lay stretched 

 on the surface. 



As in all the families of more highly organized animals, the 

 characters of individuals vary amazingly. Speaking generally, Lenz 



