THE ADDEB-SWALLOWING THEORY. 



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very full in the throat, and, on gentle pressure, I got out two 

 young Water Voles.) The mechanism of the jaws is indeed 

 peculiarly fitted for the passage of bulky articles of food, a feature 

 common to the Ophidia group. 



3rd. The cubic capacity of the oesophagus (gullet). 



This is a crucial point. If the Adder does swallow her young 

 it is to be presumed that there must be room in every average- 

 sized Adder's gullet for an average-sized family. The capacity 

 of the gullet can be estimated by the simple process of dilating 



it to its full extent with air through a blowpipe. I did this in 

 the presence of a naturalist last week ; his comment was, " There 

 is room for twenty young ones, but for forty I think not." The 

 average length of the gullet is 9 in., and the average diameter, 

 when distended, 1 in., the average circumference 3j in. Young 

 Adders can curl themselves up in a remarkable way, and I have 

 no hesitation in saying that the capacity of the oesophagus is 

 sufficient to hold the young. My conclusion is that, theoretically 

 considered, there is no anatomical reason why the Adder- 

 swallowing theory should not be true. 



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