7s BRITISH SERPENTS. 
the slough las been cast. They are the same in 
veneral character in the female, but not so brilliant. 
At the back of the head, which is flattened, there are 
two narrow dark or black bands, converging to a 
point on the top of the skull. These two dark bands 
may or may not join at the point to which they 
converge; as a rule, they do not quite join. They 
form the well-known characteristic V-shaped imark, 
the point of the V being towards the snout of the 
adder. But this V-mark, although always present in 
adders, shows endless variety. As I write, there are 
a uumber of preserved adders on the table before 
me, and on looking closely at them seriattm, it is 
noticeable that the mark is shehtly different im each 
specimen—very different, indeed, in some from others. 
The following drawing (natural size) shows some of 
these variations. The figures under each drawing 
refer to the length of the adder to which the marking 
belongs, measured in inches. These specimens were 
taken haphazard out of my collection, and they 
show well that the V-shaped mark is a very varying 
one. Immediately behind the V the adder is of a 
bright yellow colour very often, showing up the 
dark markings more prominently. Then, proceeding 
in the description along the back, the zigzag black 
line is noted, the first pateh of which is shown in 
the drawings. This first patch also varies greatly 
In shape, but as it goes along the back it becomes 
nore regular. This line of markings is continued 
