134 
Mr. Bell on the structure and use of the 
tion passes, is situated about two thirds of the length of the 
lower jaw backwards from the symphysis. It consists of a 
longitudinal slit in the integuments, a little within the edge of 
the basis of the jaw. The scales with which it is immedi- 
ately surrounded are much smaller than those which cover 
the neighbouring parts ; and it is generally concealed by a 
duplicature of the integuments, so that the skin requires to 
be extended laterally before it can be brought into view. 
Through this opening exudes an unctuous substance of a 
consistence somewhat like suet, of a brownish colour, and 
with a powerful odour exactly resembling that of musk. 
Having kept two of these animals for several months, I 
made occasional observations on this secretion, and found, as 
might have been expected, that during the warm weather, 
while they fed freely, and when all their functions were 
more perfectly developed, I could at any time procure it by 
slightly pressing the gland with the finger ; but that in the 
winter, notwithstanding they were almost constantly kept in 
a room with a fire, and daily placed in warm water, it was 
greatly diminished in quantity, and its odour much less 
powerful. 
On removing the integuments, the gland itself is seen 
closely attached to the skin, and lying between it and the 
under surface of the tongue. It consists of a simple follicle 
or sac, of a bluish colour, elongated and somewhat pyriform 
in its shape. In the alligators which I have dissected, and 
which have not exceeded four feet in length, the gland has 
been about half an inch long, and the sixth of an inch in 
diameter, its base being directed obliquely forwards and out- 
wards. On cutting open the follicle, the internal surface is 
