22 Mr. Rennie on the Cleanliness of Animals. 



< If it takes/ says he, ' any part of its prey with its foot, as I 

 have the greatest reason to believe it does chafers, (Zantheumia 

 soktitialis, LEACH, MS.,) I no longer wonder at the use of its 

 middle toe, which is curiously furnished with a serrated claw*.' 

 Mr. Dillon has recently controverted this opinion ; his observa- 

 tions leading him to suppose that the serratures are employed 

 by the bird to comb its whiskers (vibrissae)-\ . Mr. Swainson, 

 again, a high authority on such a subject, thinks that the fact 

 of an American group of the same birds (Caprimulyida), 

 which have no whiskers to comb, and an Australian group, 

 which have whiskers, but no serratures on the claws, are dis- 

 cordant with Mr. Dillon's opinion J. It frequently happens, 

 however, that the most ingenious and apparently incontrover- 

 tible reasoning in natural history, is overturned or confirmed 

 by facts accidentally observed. I was, I confess, disposed to 

 think Mr. Dillon's opinion more plausible than true, and to 

 agree with White, and the learned arguments of Mr. Swainson, 

 till I met with some observations of the distinguished American 

 ornithologist, Wilson, upon some of the transatlantic species. 

 In his description of the whip-poor-will ( Caprimulgus vocife- 

 rus), he says, ( the inner edge of the middle claw is pectinated, 

 and, from the circumstance of its being frequently found with 

 small portions of down adhering to the teeth, is probably em- 

 ployed as a comb, to rid the plumage of its head of vermin, this 

 being the principal and almost the only part so infested in all 

 birds .' 



Of another species, called chuck- will's- widow (C. Caroli- 

 nensis], he says, ' their mouths are capable of prodigious 

 expansion, to seize with more certainty, and furnished with 

 long hairs or bristles, serving as palisades to secure what comes 

 between them. Reposing much during the heats of the day, 

 they are much infested with vermin, particularly about the 

 head, and are provided with a comb on the inner edge of the 

 middle claw, with which they are often employed in ridding 

 themselves of these pests, at least when in a state of captivity ||.' 

 Considering the utility of such an instrument, we may wonder, 



* Nat. Hist, of Selborne, i. 160. Ed. Lond. 1825. 

 f London's Mag. of Nat. Hist. ii. 31. J Ibid. iii. 188. 



Wilson's American Ornithology, v. 77. || Ibid. vi. 97. 



