EXPLANATION OF THE ANATOMICAL PLATES. 
Explanation of Plate XLV. 
This Plate contains twelve figures, which represent the different appearances of the palates of innocuous and 
poisonous snakes ; and the mechanism by which the poisoning fangs are erected in different species of poisonous 
snakes. 
The four first figures represent the palates and upper jaws of the following snakes : the Tar Tutta, No. XV.; 
the Katuka Rekula Poda, No. VII.; the Cobra de Capello, No. V.; and the Bungarum Pamah, No. III.; in 
each of which there is some peculiarity respecting the teeth. 
Figure 1. The Tar Tutta, which is an innocuous snake, has in the upper jaw two rows of teeth seem¬ 
ingly situated in the palate, and one surrounding the edge of the jaw. 
Figure 2. The Katuka Rekula Poda has two rows of teeth, seemingly in the palate, but no marginal row. 
The teeth are surrounded by a fringed membrane, which almost conceals them ; the points of the teeth alone 
being exposed, unless the membrane is pressed down. The space extending from the teeth on each side, to the 
edge of the mouth at the anterior part, is filled up by a large, corrugated, membranous bag, which incloses the 
poisoning fang. On the right side, in this figure, the mouth of the bag is so much closed as to conceal the 
fang, but on the opposite side, the point of the fang is exposed. 
Figure 3. The Cobra de Capello has two rows of teeth, seemingly in the palate, and two poisoning fangs, 
differing in nothing from the Katuka Rekula Poda, but in the teeth being smaller, and the poisoning fangs 
much shorter; consequently the bags that inclose them are less conspicuous. 
Figure 4. The Bungarum Pamah has two rows of teeth, seemingly in the palate, and two poisoning fangs, 
but these are still smaller than in the Cobra de Capello. It has likewise in the margin of the mouth, on each 
side, just behind the orifice of the bag which incloses the poisoning fang, three small teeth, which are not 
met with in other snakes ; these may be considered as an imperfect marginal row of teeth. 
Figure 5, represents the skeleton of the head of the Tar Tutta. The two rows of teeth, seemingly situated 
in the palate, are fixed in that portion of the bone which constitutes the principal part of the upper jaw ; and the 
marginal row is fixed in an exterior portion, which is weaker than the other. 
In snakes, the lower jaw is not articulated with the upper, as in other animals, but by means of two bones 
connected to the occiput; the extreme points of the posterior part of the upper jaw lie exactly between and 
within the condyles of the lower, and are loosely connected to them by ligaments. By this mechanism, when 
the snake opens its mouth, the condyles of the lower jaw, moving on the occiput by these intermediate bones, 
are thrown outwards, and carry the extreme points of the upper jaw along with them, and dilate the fauces to a 
very great degree. This motion of the upper jaw also erects the fangs. 
Figure 6 , exhibits the same view of the skeleton of the head of the Katuka Rekula Poda, that is represented 
in the last figure of the Tar Tutta. The teeth and all the other parts in this snake are much larger. The two 
rows of teeth, which in the living animal appeared to be in the palate, are here more distinctly seen to be fixed 
in the bones of the upper jaw, than in Fig. 5, as there are no other teeth in it. There is a joint in the jaw bone 
of each side near its anterior extremity, which gives the appearance of its having been fractured and united 
again. There is also a large, crooked, poisoning fang, fixed in a strong bony socket: and between this socket 
and the margin of the mouth laterally, there is a slender bone connected to the socket and jaw, which corre¬ 
sponds with that portion of the jaw in which the marginal row of teeth is inserted in the Tar Tutta, as well as 
in all other innocuous snakes. 
Figures 7, 10, and 11, represent the side views of three upper jaws of different species of poisonous snakes, 
to show the mechanism by which the poisoning fang is raised and depressed, and to point out a variation in the 
