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 able as being destitute of the large intestines, the cæca, which form so large a part of the digestive canal of the common fowl and of all other true gallinaceous birds.

Nor is this the only respect in which the digestive organs of the pigeon differ from those of birds in general; for there is no gall-bladder to receive the secretions of the liver, which are poured at once into the intestinal canal.

Pigeons feed on vegetable substances, grain, pulse, the seeds of grasses, and also on green vegetables. In a wild condition they devour a great number of the smaller snails that frequent neighbourhoods of the sea-coast, their crops when shot being often found to be partially filled with these small molluscous animals. The bird when feeding fills the crop, which is a mere receptacle for food and water, with the seeds and other substances it is collecting; these are soaked and macerated in the moisture of the crop. Small portions at a time pass through the proventriculus, where they are acted on by the digestive or gastric fluid, and passed on to the gizzard, in which, by the action of its powerful muscles and the small stones it contains, they are ground to pulp. In this condition the food passes on into the intestines, where it is mixed with the bile and other secretions; and the nutriment for the support of the bird is absorbed as it passes along the canal.

The intestines of a pigeon are twice as long as those of a hawk of the same size, the nourishment not being so readily extracted from vegetable as from animal food. The canal is also much longer in comparison than that of a fowl, in which the size of the cæca compensates for its shortness. The mode of drinking followed by pigeons is very characteristic; the beak is plunged deeply into water, and a long draught taken. The quantity of water consumed by these birds is very great—much more than would serve fowls of the same size.

The pigeons usually lay two purely white eggs, in confinement sometimes only one egg is laid, but never more than two, unless, from the absence of a sufficient number of male birds, two hens pair and make a nest, when four eggs are laid, which of course are sterile, and after being sat upon for the usual period are deserted.

The young are usually covered with long yellow down, but in those domesticated varieties that have certain colours this down is absent, as in the silvery and dun birds. Thus it is easy to distinguish between a young dun and a black in the same nest, the one being naked, the other covered with profuse yellow down.

The young, which are hatched in a very helpless and immature condition, are entirely fed at first with a soft curdy secretion, which is produced in the crops of the parent birds at the end of the period of sitting.

This secretion of "soft food," as it is termed by pigeon-fanciers, cannot be delayed; consequently, if the young do not emerge from the eggs on the eighteenth day, the old birds desert the nest, refusing to sit longer on the sterile eges. The production of the soft food, however, may be hastened a day or two.