225 



and pull them in such a manner as to act upon 

 the feet, and so draw in the claws as to clasp 

 tightly the branch on which the bird is perched. 

 The claws also afford a provision for ensuring 

 cleanliness. Most birds are infested with a spe- 

 cies of louse, which, without the sharp and scrap- 

 ing claws, it were impossible they could dislodge. 

 The middle claw of some species, as the night- 

 jar and herons, are even furnished with a comb- 

 like appendage it being serrated or notched 

 along its inner edge and as this pectinated or 

 comb-like edge is frequently found with small 

 portions of down adhering to its teeth, it is na- 

 tural to suppose, that it is intended as a comb 

 to rid the plumage of the head of vermin, which 

 is the principal, and almost the only part, so in- 

 fested in all birds. Mr Ainsworth, in the second 

 number of the Journal of the Royal Institution, 

 has related several examples of this interesting 

 fact ; and a circumstance in evidence of its truth 

 presented itself last year to my own observation. 

 Attached to my stables is a large paved yard, in 

 which I attempted to keep and to rear poultry ; 

 but although the fowls when first placed there 

 were very healthy and lively, they soon became 

 weakly and sick. Corn would not fatten them, 

 and, indeed, they soon scarcely heeded to run to 

 the hand from which it was thrown. It was long 

 before I could discover the cause of all this, but 

 at last I caught a bird to examine it, and found 

 it literally covered with vermin. The paved yard 

 had blunted and rubbed down the edges of the 



