150 Dr. J. B. S. Jackson's Dissections of a 
 nication between the external air and the interior of the 
lungs; the soft palate extends very far backwards, and the 
strong muscles in that region, contracting about the larynx, 
cut off all communication between it and the cavity of the 
mouth. In the collapsed state in which the organs were after 
their removal from the body, the glottis stood erect three 
inches above the posterior edge of the soft palate, and it was 
23 inches in width, the anterior lip being the largest. It 
appeared to consist of an anterior and a posterior cartilage, 
covered by a thin membrane and by cuticle, the whole bearing 
some gross resemblance in form to a turtle's back ; down the 
back of the anterior cartilage there extended a ridge, and along 
the opposite one a corresponding groove, allowing the two to 
close very perfectly together, and superseding the necessity of 
a proper epiglottis, which organ seemed to be wanting, thoug 
it really existed in the form of the anterior cartilage. ‘The 
thyroid cartilage is 3 inches in length anteriorly, 6 inches pos 
teriorly, and the same for the width on one side; form very 
regular. Cricoid not remarkable. ; 
The blow-hole, situated on the top of the head, at the very 
extremity, and rather towards the left side, was 63 inches long, 
and in the form of an f, as observed by Alderson and also 5 
Beale. F. Cuvier says, in one part of his work, (p. 989) that 
the form is semicircular, though in a supplement, (p. 384) » 
quotes largely from Beale’s work, which was then recent, : 
so far corrects himself as to say that it has the form of an * 
The direction was longitudinal, though Hunter makes it ue | 
verse. Captain Chase states, that when the whale blows out 
the orifice becomes circular, and that in an old one he has — ; 
it as large as a bucket ; as to the formation of the spout, about : 
which there has been and is still so much question amongst T 
authors, he regards it unequivocally as the vapor of the expired : 
air with the addition of a very small quantity of water that 
gets into the blow-hole from Without, the water that 15 ik 
in with the food being discharged, he thinks, as it was rece ? 
and not through the blow-hole ; his observations, then; agree 
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