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62 
as to whether the communication was immediately - 
by the eustachian tube, for although when the blow- 
pipe was introduced into this tube there was a sens 
sible stream of air felt where the cervical air-cells 
had been opened, the throat-pouch having been like- 
wise laid open, its dependence on a supply of air by 
the eustachian tube could not be ascertained. 
While the numerous cells between the integument 
of the body derived their air immediately from 
the lungs, the throat pouch was susceptible cf in- 
flation totally independent of supplies from the tha- 
racic cavity. 
The air which had been blown into the lungs by 
the trachea had passed into the body generally, for 
“when these parts were opened, they were found to. 
be highly inflated and the vessels and nerves inter- 
secting the transparent sepia in their efftce of form. 
ing the cellular air-cavities, between the skin and 
the subjacent muscles, were beautifully exhibited in 
their passage, fom the interior to the exterter por- 
tions of tlie body. . 
Y observed, in the living bird that as the throat 
pouch, which is bare of feathers, was at any time dis- 
tended with air, the skin increased in intensity of 
colour and changed from a duli dirty rouge, to a 
deep brilliant red, deepening in hue, as the pouch 
swelled in volume. This no doubt resulted from the 
change which the blocd underwent, in the capillary 
vessels of this great receptacle. The systemaée cir- 
eulation in this part, was acted upon by the exyge- 
nated air in the great cells of the throat, this air 
oeing derived Immediately from the atmosphere, 
