640 Habits of the Vultur Aura. 



dead dog was concealed in a narrow ravine, 20 ft. below the 

 surface of the earth around it, and filled with briers and high 

 canes ; that many vultures were seen sailing in all directions 

 over the spot, but none discovered it. I may remark upon the 

 above experiments, that, in the first case, the stag was doubt- 

 less seen by the birds ; but it does not follow that they might 

 not also have smelt the hide, although inodorous to the human 

 nose. In the second case, the birds had undoubtedly been 

 attracted by smell, however embarrassed they might have been 

 by the concealment of the object which caused it. I have, in 

 many hundred instances, seen the vulture feeding upon small 

 objects under rocks, bushes, and in other situations where it 

 was utterly impossible that the bird could have discovered it 

 but through the sense of smell ; and we are to recollect that 

 the habit of the vulture is that of soaring aloft in the air, and 

 not that of foraging upon the ground." 



Mr. Sells's communication was accompanied by the follow- 

 ing letter from Mr. Owen, addressed to the secretary, W. 

 Yarrell, Esq. 



" Dear Sir, I received the heads of the John Crow, which 

 I suppose to be the Vultur Aura, or turkey buzzard ; and 

 have dissected the olfactory nerves in both ; as also in a turkey 

 which seemed to me to be a good subject for comparison, 

 being of the same size, and one in which the olfactory sense 

 may be supposed to be as low as in the vulture, on the sup- 

 position that this bird is as independent of assistance from 

 smell in finding his food as the experiments of Audubon 

 appear to show. There is, however, a striking difference be- 

 tween the turkey vulture and the turkey in this part of their 

 organisation. The olfactory nerves in the vulture arise by 

 two oval ganglions at the anterior apices of the hemispheres, 

 from which they are continued 1 J line in transverse diameter, 

 and 2 lines in vertical diameter, and are distributed over 

 well-developed superior and middle spongy bones, the latter 

 being twice the dimensions of the former. The nose is also 

 supplied by a large division of the supraorbital branch of the 

 5th pair, which ascends from the orbit, passes into the nose, 

 crossing obliquely over the outer side of the olfactory nerve, 

 extending between the superior spongy bone and the mem- 

 brane covering the middle spongy bone ; then descending, 

 and, after supplying the inferior and anterior spongy bone, 

 escaping from the nasal cavity to supply the parts covering 

 the upper mandible. This olfactory branch of the 5th pair 

 is about ^th the size of the true olfactory nerve. 



" In the turkey, the olfactory branch of the 5th nerve is 

 about the same size as in the vulture, and is superior in size 



