Columbidæ.
The Columbidæ family establish a transition between real Gallinaceans and Passerines; in short, they partake of the nature of both. Whilst they approach the former in their anatomical and purely material characteristics, such as the structure of their beaks, sternum, and crops, they resemble the latter in their elegant forms, peaceable manners, and in all their habits.
Like the Passerines, they are monogamists. The male and female build their nests together, and share the cares of the incubation and education of their young; these, when born, are blind, and only covered with a slight down, and are quite unable to run like young Gallinaceans. There are generally two Pigeons hatched at the same time; and it is a very curious fact that there is almost always a male and a female. They do not quit the nest till they have acquired sufficient strength to use their wings and fly. During the earliest portion of their existence they receive no other nourishment from their parents than a sort of pap secreted in the walls of the gullet; but at the end of some days the father or mother discharges into their beaks the food which they themselves take. When they are sufficiently developed, they travel with the adults in large flocks to seek a milder climate or better feeding ground: their migrations in the natural state occur in spring and autumn. What distinguishes them from the true Gallinaceans is that they have a thumb inserted even with the other toes, and that consequently they are able to perch; almost all Pigeons pass much of their lives on trees. Their food consists principally of seeds, berries, and fruits, sometimes insects, and a peculiar little snail similar to that found in the Isle of France. Their flesh, generally good, in some species, such as the Crowned Goura, acquires an exquisite flavour. Thus they form an immense part in public alimentation, both in a domestic and wild state. They are shot very extensively at the time of their migration. Although their flight is noisy, and even presents some appearance of heaviness, it is easy and sustained, so that Pigeons have been known to accomplish journeys of surprising length in a few hours.
We will divide the Pigeons into three families—the Colombi-Gallines, the Colombes, or, properly speaking, Pigeons, and the Colombars.