518 The Rev. Revett Siieppard on the Use 



of climbing; more especially when we consider that the Nut- 

 hatch (Sitta europaa) and Tree-creeper (Certhia familiaris) have 

 their toes placed in the usual manner, and jet run up and 

 down trees with as much facility as the Woodpeckers. The use 

 of the pedes scansovii^"', then, to the Cuckow (as they evidently, in 

 this case, conduce not to climbing,) I judge to be this : It is well 

 known that this bird will oftentimes sit by the half-hour together 

 on the bough of a tree vociferating its loud and pleasing note; in 

 doing this it sits remarkably forward, and appears in constant 

 agitation, continually moving its body up and down with great 

 elegance : now, as it sits so forward whilst using this exertion, it 

 would be liable to lose its balance and quit its hold, had it only 

 one toe behind ; whereas, by the contrivance of two, it is enabled 

 strongly to adhere to the branch. 



Psittaciis also has the pedes sconso)-ii, and is actually a climbing 

 genus; yet does not this conformation in my opinion in any man- 

 ner conduce thereto. To say that Parrots assist themselves with 

 their beaks in climbing, would not argue the pedes scansorii to be 

 of no utilit}'. Their real use to this genus seems to be not only 

 to grasp their food (for the foot of the Parrot serves the purpose 

 of a hand in that respect), but to enable them to step securely 

 from one branch to another, and likewise to hang suspended, as 

 they often do ; in which case the two toes before and two behind 

 certainly give stability to their hold. 



With respect to the Fici, rather a clumsy tribe, the very stiff 

 feathers in the tail are of material service to prop them up in the 

 act of climbing : not so the pedes scansorii, for the Nuthatch with- 

 out them runs up trees equally well. Of what use then can these 

 be to the AVoodpecker? 1 answer, that in boring trees, (in which 



* 1 think a more appropriate term might be adopted for this peculiar conformation ; 

 Riid for this purpose 1 take tiie liberty of suggesting the word comprehensorii, 



occupation 



