of the Pedes scansorii of Birds. 519 



occupation the bird is often engaged for a considerable length of 

 time), its weight is thrown backward, and thns the supply of two 

 toes behind is rendered extremely necessary for its support. 



AVhat makes me think the wise Author of Nature had this end 

 principally in view is, that the Nuthatch, from the want of this 

 conformation, is, when breaking nuts, under the necessity of sit- 

 ting with its head downwards. It may be alleged that its flexible 

 tail compels it to this position ; but, as I have before observed, 

 it runs up trees with equal or greater facility than the Wood- 

 pecker, notwithstanding that disadvantage. 



It would be a curious circumstance, and a conclusive argu- 

 ment in my favour, should it ever be ascertained that the three- 

 toed "Woodpecker {Picas tridactylus*), which has only one toe 

 behind, bores trees in the attitude assumed by the Nuthatch 

 when breaking nuts. 



I have now brought this letter, which I fear has tired your pa- 

 tience, to a conclusion ; but as it is upon a subject hitherto not 

 sufficiently examined into, you may possibly think it worthy of 

 being communicated to our scientific brethren. 



I am, &c. 



Wrabness Parsonage, RevETT ShEPPAUD. 



April 15, 1818. 



* Linnaeus, in his description of the Vkiis iridactylus, says, " Europaeus vertice flavo, 

 Americanus rubro est." It is worthy of observation, that a fine specimen, brought by my 

 brother Edmund Sheppard, Esq., of the Royal Artillery, (whose assiduity in collecting sub- 

 jects of natural history when abroad, entitles him to great credit,) from Drummond's Island, 

 in Lake Huron, Upper Canada, has the crest, like the European species, of a bright yellow. 



XXXII. An 



