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 httle 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 suecess 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- 
appomlinent. 
The average number of young.—It might be 
inavined that on this point there would be some 
devree of agreement amonest 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 eiven in the third-quoted esti- 
K 
