The vulture and the heavier wild birds can only fly after taking a run, or else by commencing their flight from an elevated spot. They use the tail by way of rudder. There are some birds that are able to see all around them; others have to turn the neck to do so. Some of them eat what they have seized, holding it in their feet. Many, as they fly, utter some cry, while others are always silent. Some fly with the breast half upright, others with it held downwards, others fly obliquely, or side-ways, and others follow the direction of the bill. The fact is, that if we were to see several kinds at the same moment, we should not suppose that they were adapted to the same element.
Those birds which are known as “apodes”[178] fly the most of all, because they are deprived of the use of their feet. They are a species of swallow which build their nests in the rocks, and are the same birds that are to be seen everywhere at sea. However far a ship may go, however long its voyage, and however great the distance from land, the apodes never cease to hover around it. Other birds settle and rest, but these know no repose save in the nest; they are always either on the wing or asleep.
The instincts of birds are no less varied in relation to their food. The “Caprimulgus,” or goat-milker, is the name of a bird, which is to all appearance a large blackbird; it thieves by night, as it cannot see during the day. It enters the folds of the shepherds, and makes straight for the udder of the she-goat, to suck the milk. Through the injury thus inflicted the udder shrivels away, and the goat that has been thus deprived of its milk, is afflicted with incipient blindness.
“Platea,” or spoon-bill, is the name of another, which pounces upon other birds when they have dived in the sea, and, seizing the head with its bill, makes them let go their prey. This bird will swallow and fill itself with shell-fish, shells and all, and after the natural heat of its crop has softened them, it will bring them up again, pick out the shells from the rest, and choose the parts that are fit for food.
[Illustration: SPOTTED KING FISHER.—_Céryle Guttáta._]
The farm-yard fowls have a certain notion of religion; upon laying an egg they shudder all over, and then shake their feathers; after which they turn round and purify[179] themselves, or else hallow[180] themselves and their eggs with some stalk or other. The carduelis, which is the very smallest bird of any, will do what it is bid, not only with the voice but with the feet as well, and with the beak, which serves it instead of hands. There is one small bird, found in the territory of Arelate, that imitates the lowing of oxen, from which circumstance it has received the name of “taurus.” Another, called the anthus, imitates the neighing of the horse; upon being driven from the pasture by the approach of the horses, it will mimic their voices—taking this method of revenging itself.