294 OBSERVATIONS ON INSECTS AND VERMES. 
formed from its own saliva ; so that it is perfectly secured, and 
corked up as it were, from all inclemencies. The cause why the 
slugs are able to endure the cold so much better than shell- 
snails is, that their bodies are covered with slime as wales are 
with blubber. 
Snails copulate about Midsummer; and soon after deposit 
their eggs in the mould by running their heads and bodies under 
ground. Hence the way to be rid of them is to kill as many as 
possible before they begin to breed. 
Large, gray, shell-less, cellar snails lay themselves up about 
the same time with those that live abroad ; hence it is pla^n that 
a defect of warmth is not the only cause that influences their 
retreat. 
SNAKE'S SLOUGH. 
There the snake throws her enamell'd skin. 
ShakspearCy Mids. JVighVs dream. 
About the middle of this month (September) we found in a field 
near a hedge the slough of a large snake, which seemed to have 
been newly cast. From circumstances it appeared as if turned 
wrong side outward, and as drawn off backward, like a stocking 
or woman's glove. Not only the whole skin, but scales from 
the very eyes, are peeled off, and appear in the head of the 
slough like a pair of spectacles. The reptile, at the time of 
changing his coat, had entangled himself intricately in the grass 
and weeds, so that the friction of the stalks and blades might 
promote this curious shifting of his exuviae. 
Lubrica serpens 
Exuit in spinis vestem." Lucret. 
It would be a most entertaining sight could a person be an 
eye-witness to such a feat, and see the snake in the act of 
changing his garment. As the convexity of the scales of the 
eyes in the slough is now inward, that circumstance alone is a 
proof that the skin has been turned : not to mention that now 
the present inside is much darker than the outer. If you look 
through the scales of the snake's eyes from the concave side, 
viz. as the reptile used them, they lessen objects much. Thus 
it appears from what has been said, that snakes crawl out of the 
mouth of their own sloughs, and quit the tail part last, just as 
eels are skinned by a cook maid. While the scales of the eyes 
