“The pelican seems to me a wise fisher,” remarked Emile. “Without losing a minute in swallowing, it begins by filling the bag under its beak. The time will come later for looking over the catch and enjoying the fish at leisure. I should like to see it on its rocks with its bag full.”
“And that other one,” said Jules, “that throws the fish it has caught into the air so as to catch it again head first and not strangle when swallowing it—is not that one just as clever?”
“Each kind has its special talent,” replied Uncle Paul, “which it uses with the tool peculiar to the bird, the beak. If the story of the auxiliaries, related some time ago, is still fresh in your minds, you will remember that insect-eating birds have the beak slender and sometimes very long, to dig into the fissures of dead wood and bark; but those that catch insects on the fly, as the swallow and the fern-owl, have the beak very short and exceedingly wide, so that the game pursued is caught in the open gullet and becomes coated with a slimy saliva which holds [[16]]it fast. Finally, I will remind you of the granivorous birds—the sparrow, linnet, greenfinch, chaffinch, and many others. All these birds, whose chief food consists of grain, have the beak short, thick, pointed; adapted, in fact, to the picking up of seeds from the ground, freeing them from their husks, and breaking their shells to obtain the kernel. By virtue of its strong mandibles, the beak of the hen belongs to this last category, although at the same time its rather long, sharp, and slightly hooked extremity indicates carnivorous tastes. Such a beak calls not only for seeds, but also for small prey, such as insects and worms.” [[17]]
CHAPTER II
THE GIZZARD
“Nearly all the higher or mammiferous animals,” Uncle Paul continued, “such as the dog, cat, wolf, horse, have only one digestive pouch—a stomach—where the alimentary substances are dissolved and made fluid, so as to enter the veins and be turned into blood, by which all parts of the body are nourished. But the ox, goat, and sheep—the cud-chewers, in short—have four digestive cavities, which I will tell you about later. I will tell you how, in the pasture, these animals hastily swallow almost unchewed grass and put it by in a large reservoir called a paunch, from which it comes up again afterward in a season of repose, to be rechewed at leisure in small mouthfuls.
“Well, birds are fashioned in a similar way, as far as eating is concerned. Not being able to chew, as they have no teeth, they swallow their food without any preparation, nearly as the beak has seized it, and amass a quantity of it in a spacious stomach, just as the ox does in his paunch. From this reservoir the food passes, little by little, into two other digestive cavities, one of which immerses it in a liquid calculated to dissolve it, and the other grinds and triturates it better than the best pair of jaws could [[18]]do. There takes place a kind of chewing, it is true, only the food, instead of returning to the beak, where teeth are lacking for its thorough mastication, continues its journey, and on the way comes to the triturating machine. Birds, then, are generally provided with three digestive cavities.
“The first is the crop, situated just at the base of the neck. It is a bag with thin and flexible walls, its size proportioned to the resistant nature of the food eaten. It is very large in birds that feed on grain, especially the hen, and is medium-sized, or even wholly wanting, in those that live on prey, which is much easier to digest than dry and hard seeds. In the crop, the food swallowed in haste remains hours and even days, as in a reservoir; there it softens somewhat, and is then submitted to the action of the other digestive pouches. The crop corresponds in a certain sense to the bag in which the pelican stores up his fishing; it represents also the first stomach of the ox and the other cud-chewers or ruminants.
“Next to the crop is a second enlargement, called the succenturiate ventricle, of small capacity but remarkable for a liquid of a bitter taste that oozes in fine drops through its walls and moistens the food as it passes. This liquid is a digestive juice; it has the property of dissolving the alimentary substances as soon as trituration has done the greater part of the work. The food does not remain in this second stomach; it merely passes through to become impregnated with the digestive juice.