THE DESERT SNAKES. 47 
covering of the eyes and that of the scales are always found in the 
exuviz. Previous to this curious phenomenon, the whole cuticle 
becomes somewhat opaque, the eyes dim, and the animal is evidently 
blind ; it also becomes more or less inactive, until at length, when the 
old skin is ready for removal and the new skin perfectly hard under- 
neath, the animal bursts it at the neck, and creeping through some 
dense herbage or low brushwood, leaves it detached, and comes forth 
in brighter and clearer colours than before.” 
The Ringed Snake begins to hybernate about the end of autumn, 
when they coil themselves up, sometimes in numbers, till the spring 
again calls them forth. Many instances are told of this Snake 
_ being tamed. Mr. Bell had one which knew him from all other 
persons ; it would come to him when let out of its box, crawl under 
the sleeve of his coat, and every morning visit him for a draught of 
milk. 
iA Green and Yellow Snake is also about a yard in length, and 
is common in the south and west of France; they have been taken 
in the forest of Fontainebleau. The beautiful colours in which they 
are clothed causes them to be easily distinguished from the Viper. 
The eyes are edged with golden-coloured scales ; the upper part of 
the body is of a very dark greenish colour, upon which is extended 
a large number of radiating lines, composed of small yellowish spots 
of different shapes, some long, others lozenge shape, giving it a 
chequered. appearance. ‘These chequers extend from the head to the 
tail. The belly is yellowish ; the large plates which cover it have a 
black spot at each end, and are bordered with a very thin black line. 
This inoffensive reptile is extremely timid, and generally hides itself 
from observation, taking to flight at the least alarm. ‘They are said 
to be easily tamed. 
The Viperine Snake (Zrofidonotus viperinus, Fig. 12) has the 
body of a greyish or dirty yellow colour, having on the middle of the 
back a series of blackish spots so close to each other as to give the 
idea of one small continuous wavy line from head to tail. The sides 
are covered with isolated spots, forming lozenge-like figures, the 
centres of which are of a greenish tint. This is the smallest of all 
the European Colubride, and, like the others, it is found in most 
parts of Europe. 
[The Psammophid@, or Desert Snakes, are akin both to the 
Colubrid@ and to the Tree Snakes of the next family ; but the latter, 
remarks Dr. Giinther, may always be distinguished either by their 
green coloration, by the horizontal pupil of the eye, or the absence 
‘of a long anterior maxillary tooth. In the Psammophide the pupil 
