96 



CHAPTEli vnr. 



THE ADDER— Continued. 



ANATOMY. 



ANATOMICAL POINTS — PLATES AND SCALES — JAWS — POISON- 

 FAN*; — WINDPIPE — GULLET — STOMACH — HEART, LUNGS, 

 AND LIVER. 



Anatomy. — Except that the adder is a poisonous 

 serpent, all the negative characteristics of the Ophidia, 

 which were noted under the anatomy of the ring 

 snake, are again to be remarked in the adder. But 

 there are some positive differences to be noted, and 

 some points common to both these snakes not referred 

 to previously. 



Plates and scales. — The plates on the head in 

 this species are more numerous than in the ring snake, 

 and have quite a different arrangement. They are 

 also smaller, with the exception of one large plate 

 between the eyes, often the only light-coloured spot 

 on the top of the head. The position of this plate 

 is shown in two of the drawings of the V-shaped 



