80 AMPHIBIA. 
unknown.) Ribs very short. Sternum wanting. Ears 
concealed. Impregnation probably internal. 
Genus. Cacilia. 
I do not offer this arrangement either as wholly original, 
nor as absolutely natural ; but it appears to me to be less 
objectionable than the others which have been proposed. 
It is exclusively to the first and second order that the 
few Amphibia which are indigenous to this country be- 
long; and I shall confine my observations on the general 
characters of the class, and on their physiological peculi- 
arities, to those points which may be illustrated by a 
reference to our own native species. The most striking 
external character by which the whole of these animals 
are distinguished is the naked skin. Whilst all the true 
Reptilia are covered by some hard and corneous, or, at 
least, coriaceous modification of the cuticle, which appears 
in the form of plates, as in the Crocodiles and Tortoises, 
and in that of scales, as in the Lizards and Serpents, the 
Amphibia have no vestige of such a structure ; the skin 
being in all cases soft and smooth, and in many instances 
always more or less moist. Some of them, as the Sala- 
manders aud the Toads, have a number of cutaneous 
glands which secrete a viscid fluid, which is said to be 
more or less acrid and irritating. This is most conspicu- 
ous in the common Salamander of Europe, which when 
irritated will often throw out from these glands a quantity 
of such white and tenacious fluid. Now the acrid quality 
of this secretion forms the sole ground for the reputed 
poisonous character of these animals ; for it is a well ascer- 
tained truth that not one of them possesses any organ by 
which poison can possibly be communicated. The cuticle 
is frequently shed, and in various modes, according to the 
