138 SNAKES. 



them began to eat his before it was quite dead, and had 

 finished it before his friend had begun. In his case, the air- 

 pipe was at the side of his distended jaws. In the other, it 

 projected more than half an inch beneath, nearly in the 

 centre. 



This happened on a mild, damp day in November 1873, 

 and after that I saw the tube in ' several snakes,' but I 

 regret the names were not entered in my notebook at the 

 time. In the smaller non-venomous snakes, or in the lacer- 

 tines — of which there were then a large number — I do not 

 remember to have observed it. They despatch their frog 

 or mouse so quickly that they would scarcely need a fresh 

 supply of air meanwhile. In the larger vipers, rattlesnakes, 

 and constrictors, the air-tube was undoubtedly witnessed. 

 Winter then terminated my observations, and afterwards a 

 prolonged absence from town. Unfortunately, when ob- 

 servations were about to be resumed, the change of the plans 

 at the Zoological Gardens, and the exclusion of the public, 

 defeated my intentions, though on one occasion I did see 

 the windpipe of little Matrix torquata very distinctly ; and 

 this was the smallest snake in which I had ever observed it. 

 Natrix had nearly disposed of a large frog. The whole of 

 it was in his mouth, which was widely expanded, and the 

 air-tube was protruded sideways, not oict of the mouth, but 

 sufficiently forward to enable one to distinguish its form, and 

 the action of the petite languette. The prey being unusually 

 large, the snake had needed air while swallowing it. 



On several occasions in snakes recently dead, and of 

 various sizes, one has been able to notice how admirably 

 this tube, which lies along the mouth like a soft cushion, 



