and of a new British Species of Viper. 55 
perfect form in the water, affords good reason for supposing that 
their situation on land is at once both irksome and unnatural to 
them. 
My Lacerta maculata appears to be only what Linnaeus has de- 
scribed as the larva of Lacerta vulgaris, but merely, I suppose, 
from the two dark lines which reach from the head to the end of 
the tail. My specimens are, however, in a perfect state without 
fins : and the larvae which I have seen have, like L. palustris, a fin 
upon the back, and above and below the tail : they are also co- 
vered with large dark spots. This, as well as the former species, 
will take a bait either in a perfect or a larva state. 
Lacerta vulgaris I have seen of all sizes, from one to four inches 
in length, but never in any other than a perfect state : a sufficient 
proof that, like the rest of the land lizards, it undergoes no 
change ; and that it is perfectly distinct from L. palustris, and 
L. maculata, both of which attain to their full growth in the larva 
state. 
From these observations on the genus Lacerta, I proceed to 
the description of a beautiful species of Coluber that I have lately 
discovered, to which I have given the name of Caruleus, from the 
elegant azifre blue of its belly. This certainly deserves to be 
ranked as a distinct species full as much as C. Prester. When I 
killed the animal I took down an account of the scuta and 
squamae, which I have since lost. They differed in number from 
those both of C. Berus and C. Prester ; but among the great num- 
bers of snakes and vipers that I have killed and examined, 1 
scarcely ever found two of the same species that had a like num- 
ber of scuta and squamae : a sufficient indication how imperfect 
a part of the specific character these form. 
coluber 
