GREENLAND VOYAGE. 
sound, which, in tlie beluga, may be perceived 
before the animal arises to the surface of the 
* water*. ; ; 
The external blowholes or spiracles, were, in 
the sucking whale, 4 inches in length; in the full 
grown animal, they form two curved slits, above 
10 inches long. In passing downward through 
the blubber, the blowholes, which at the surface 
are nearly longitudinal, as in the annexed figure 
Posterior. 
Anterior. 
■a, a, twist into a semi-circular and transverse posi¬ 
tion, in the form of the dotted line b b ; then pe- 
netrating the skull, they proceed backward and 
downward in two conical parallel canals, un¬ 
til they open near the back of the under-part of 
the skull, where they inosculate, and form a single 
membranous sac, within a few inches of the epi¬ 
glottis. The first impression of each blowhole on 
the upper part of the skull, is marked by an ob¬ 
long cavity b b in the following cut (represent¬ 
ing the upper surface of the anterior part of the 
whale’s skull, the skin and fat being removed;) 
* Captain Pariiy’s “ Voyage for the Discovery of a North¬ 
west Passage," p. 35. 
