SMELL. 75 



out their meat the most. But then I discovered 

 none of these nerves in round-billed birds. But since, 

 in my anatomies in the country, in a rook, I first 

 observed two nerves that came down betwixt the eyes 

 into the upper bill, but considerably smaller than any 

 of the three pair of nerves in the bills of ducks, but 

 larger than the nerves of any other round-billed birds. 

 And it is remarkable that those birds, more than any 

 other round-billed birds, seem to grope for their 

 meat in cow-dung*." " I observed," says Dr. Mou- 

 lin, " three pair of nerves in all the broad-billed 

 birds that I could meet with, and in all such as feel 

 for their food out of sight, as snipes, woodcocks, 

 curlews, geese, ducks, teals, widgeons, &c. These 

 nerves are very large, equalling almost the optic 

 nerve in thickness. Two are distributed nigh the 

 end of the upper bill, and are there very much ex- 

 panded, passing through the bone into the membrane, 

 lining the roof of the mouth f.'' 



The facts thus proved by the structure of the organ 

 are corroborated by the actions of the birds themselves. 

 There can be little doubt indeed that animals may 

 sometimes be deceived into eating what is unwhole- 

 some, or even poisonous J. But this, it is probable, 

 happens much more rarely in those endowed with 

 acute smell than in others ; for according to the 

 beautiful remark of Cicero, borrowed, it is highly 

 probable, from the Greek philosophers, " the nostrils 

 are providentially placed high because odours have a 

 tendency to rise, and are also near the mouth for the 

 purpose of discriminating food and drink ." Even 

 very young ducks, accordingly, as we have more 

 than once observed, will reject from the mud in which 



* Phil. Trans. No. 206. 



f Ibid. No. 199, or Lowthorp'? Abridg.ii. 861-2. 



I See Insect Trans, p. 76-8 ; Ins. Miscell. p. 30. 



De Natura Deorum, ii. 56, 



