THE ADDER. 145 



they are apt to retire to a warm secluded spot, there 

 to await the advent of their offspring. I noticed this 

 particularly in the case of three females that I had 

 been watching for a couple of months in their haunt. 

 During July and August they were always to be found 

 on a warm afternoon sunning themselves in the same 

 spot ; and by sitting very quietly a little distance off, 

 with a good pair of field-glasses, they could be observed 

 without much difficulty, by the exercise of a consider- 

 able amount of patience, a virtue the absence of which 

 is fatal to any success in the observation of adders in 

 nature. But at the end of August they vanished into 

 the fern and were seen no more, to my great dis- 

 appointment. 



The average number of young. — It might be 

 imagined that on this point there would be some 

 degree of agreement amongst various authors. In- 

 stead of anything like unanimity prevailing, however, 

 most widely varying figures are given in different 

 books. The three following estimates are from three 

 modern works. The adder is said to bring forth at a 

 birth young to the number of from 5 to 14, from 10 

 to 20, and from 15 to 40. The one estimate may 

 almost be said to begin where the other leaves off. 

 The minimum figure in the last estimate is greater 

 than the maximum of the first, and the maximum 

 of the first less than the minimum of the third, while 

 the maximum family allowed in the second case is 

 exactly half of that given in the third-quoted esti- 



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