168 BRITISH SERPENTS. 



Tliis is a most pressing objection ; for if it could be 

 shown that the gullet of the adder is not capacious 

 enough to contain the average number of young in an 

 adder family, then there could be but little belief in 

 the theory. Three factors are involved in this objec- 

 tion : — 



A. The average number of young in a litter. 



B. The structural adaptability of the gullet for 



swallowing. 



C. The absolute cubic capacity of the gullet. 



A. The question of the average number of the 

 young has been discussed, and the conclusion stated 

 that it is about thirteen. Here it is evident how 

 important it is to have definite data to go upon. . It 

 is not sufficient to know that an adder could hold 

 half-a-dozen young at a time in her gullet. If this is 

 nature's method of protecting them, the conditions 

 must be such as will apply universally. Not that a 

 small female adder must be able to hold in her gullet 

 the largest litter of young adders that has been re- 

 corded, but that an average-sized adder's gullet nmst 

 be capable of holding an average-sized adder's family. 



B. The question of the structural adaptability of 

 the gullet to swallow the young may be dismissed 

 with the remark that the gullet is adapted for swal- 

 lowing very large articles of diet. This matter is also 

 gone into in the consideration of adder anatomy, and 

 presents no difficulty which can be said to apply to 

 swallowing the young. 



