Zoological Society. 155 



air has been particularly noted by Mr. Hunter in his celebrated 

 Paper on the air-cells of Birds, in which he throws out a suggestion 

 that it may assist the birds of this species in carrying heavy loads 

 in their large fauces. This supposed relation of extended air-cells 

 to a largely developed beak is borne out in the case of the Hornbill, 

 in which every bone of the skeleton is permeated by air, but is ap- 

 parently contradicted by the Gannet : I say apparently, because, al- 

 though the rami of the lower jaw do not, in this species, afford sus- 

 pension to a capacious reservoir as in the Pelican, yet the bird may 

 occasionally have to bear away a considerable load, as, for instance, 

 in a large fish seized by its mandibles, and a previous accumulation 

 in its dilatable oesophagus. 



" Mr. Hunter, it may be remembered, was doubtful on the first pub- 

 lication of his Paper as to the source from which the mandibles de- 

 rived their gaseous contents : not that he was ignorant of the air- 

 holes in the bones, as he is careful to tell us in the reprint of the 

 Memoir in the ' Animal (Economy', where he states that the lower 

 jaw of the " Pelican is furnished with air, which is supplied by means 

 of the Eustachian tube." 



" To ascertain the correctness of this description I sawed across 

 the left ramus of the lower jaw ; but on blowing into the end of the 

 part attached to the head, I found that the air did not escape as I 

 had expected by the Eustachian tube, (the orifice of which is a slit, 

 situated on the roof of the mouth, one inch behind the posterior or in- 

 ternal nares,) but filled, first the air-cells under the throat, and then, 

 passing down the neck, raised the large air-cell above the fur culum. 

 On dissection I found that the air passed into the lower mandible 

 immediately from an air-cell surrounding the articulation between 

 the jaw and os quadratum ; which received its air from the lungs by 

 means of the cells passing along the neck and throat, &c. The au- 

 thority of Mr. Hunter ought not to be set aside by the result of a 

 single experiment ; and the possibility of accidental rupture may be 

 urged against the above observation ; but it is at all events worthy 

 of being recorded, and should be repeated when opportunity occurs, 

 with the addition of blowing into the Eustachian tube, which I 

 omitted to do. 



" There is little to be added to the accounts already given in the 

 works of Cuvier, and of Professor Tiedemann and Cams, of the di- 

 gestive organs of the Pelican. The weak or thin- coated stomach, 

 small c<eca, and short intestines bespeak its animal diet, and the uni- 

 formly capacious oesophagus, as well as the superadded faucial bag, 

 may be regarded as pointing to the piscivorous habits of this singu- 

 lar species. It is more difficult to assign the use of the globular 

 cavity interposed between the gizzard and the duodenum, which the 

 Pelican has in common with some of the piscivorous Grallde, viz. those 

 of the genus Ardea. In them the pyloric cavity is very small, but 

 in the Pelican it is fully as large in proportion as in the Crocodiles, 

 which alone possess it among Reptiles. In the Pelican here described 

 the pyloric cavity measured 1-} inch in diameter, communicated by 

 a small transverse aperture with the gizzard, and by an opposite one, 



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