Struclure and Oeconomy of Whales. 421 
Porpoife, Grampus, and Bottle-nofe. At its beginning in the 
fauces, it is a roundifh hole, furrounded by a flrong fphindler 
mufcle, for grafping the epiglottis ; beyond this, the canal 
becomes larger, and opens into the two paffages in the bones 
of the head. This part is very glandular, being full of fol- 
licles, whofe duels ramify in the furrounding fubftance, which 
appears fatty and mufcular like the root of the tongue, and 
thefe ramifications communicate with one another, and contain 
a vifeid (lime. 
In the Spermaceti Whale, which has a fingle canal, it is 
thrown a little to the left fide. After thefe canals emerge 
from the bones near the external opening, they become 
irregular, and have feveral fulci palling out laterally, of 
irregular forms, with correfponding eminences. The ftruc- 
ture of thefe eminences is mufcular and fatty, but lei's muf- 
cular than the tongue of a quadruped. 
In the Porpoife there are two fulci on each fide ; two large 
and two final], with correfponding eminences of different 
lhapes, the large ones being thrown into folds. The Spermaceti 
Whale has the leaft of this fcruclure; the external opening in 
it comes farther forwards towards the anterior part of the head, 
and is confequently longer than in others of this order. Near 
to its opening externally, it forms a large fulcus, and on 
each fide of this canal is a cartilage, which runs nearly its 
whole length. In all that I have examined, this canal, for- 
wards from the bones, is intirely lined with a thick cuticle of 
a dark colour. 
% 
In thole which have only one external opening, it is tranf- 
verfe, as in the Porpoife, Grampus, Bottle-nofe and Sperma- 
ceti Whale, &c. ; where double, they are longitudinal, as in 
the Piked Whale, and the large Whalebone Whale. Thefe 
openings. 
