31 G Columbidce. 



plan widely different from what we see in other birds, ' the toes 

 being short, and strengthened by a membrane connecting them 

 at the base, with the hind toe either entirely wanting or but im- 

 perfectly developed. Where this latter does exist, it is not 

 articulated upon the same plane as the other toes (as is the case 

 with the preceding Orders), but upon the tarsus, at a height 

 greater or less according to the running powers of the species.'* 

 It is true that this peculiar formation of the foot impedes tho 

 members of this Order from grasping a perch with the same 

 firmness and security as the regular perchers, and for this reason 

 most of them roost upon the ground. 



Such are the more prominent characteristics of the Ground- 

 birds; I pass on now to describe the four families and their 

 respective species of which this Order is composed. 



COLUMBID.E (THE DOVES). 



It will at once be seen that the Doves occupy an intermediate 

 place between the Perchers and the Ground-birds ; and are the 

 connecting link, partaking of the peculiarities of both : thus, 

 though they feed on the ground, they perch readily on trees; and 

 though they walk with ease and even celerity, yet they have a 

 strong, rapid and protracted flight. Thus we pass gradually and 

 almost insensibly from the true Perchers to the typical Ground- 

 birds, for Nature abhors an abrupt wrench as much as a vacuum, 

 and all is orderly, gentle, and harmonious in her arrangement, and 

 we slide on from order to order, and from family to family, 

 and genus and species in successive steps, with no break to 

 disconnect the regular links in our continuous chain. This is 

 sufficiently perceptible in the Doves, even in the limited number 

 of species which belong to this country, and almost all of which 

 (or four out of five) are known in Wiltshire. But if we were 

 to extend our observations through the multitudinous species 

 and even genera which inhabit other countries, we should see this 

 rule very much more applicable, for the Pigeons form a vast 



c Selby's ( Illustrations of British Ornithology,' vol. i., p. 403. 



