. Outlines of zoology. Zoology. ORGANS OF CROCODILIANS. 5«S ward and inward, and have a cartilaginous symphysis; the ischia slope backward and have a symphysis ; ilia and ischia form almost the whole of the acetabulum, a small part being occupied by the true pubes. The hind-limbs bear four digits, webbed and clawed. Organs of Crocodilians.—The Crocodilians are seen to best advantage in the water, swimming by powerful tail-strokes. The limbs are too weak for very effective locomotion on land, the body drags on the ground, and the animals are stiff-necked. Although many, especially in their yout
. Outlines of zoology. Zoology. ORGANS OF CROCODILIANS. 5«S ward and inward, and have a cartilaginous symphysis; the ischia slope backward and have a symphysis ; ilia and ischia form almost the whole of the acetabulum, a small part being occupied by the true pubes. The hind-limbs bear four digits, webbed and clawed. Organs of Crocodilians.—The Crocodilians are seen to best advantage in the water, swimming by powerful tail-strokes. The limbs are too weak for very effective locomotion on land, the body drags on the ground, and the animals are stiff-necked. Although many, especially in their youth, feed on fishes and small animals, the larger forms lurk by the edge of the water, lying in wait for mammals of considerable size. These they grasp in their extremely powerful jaws, and drown by holding them under water. If the dead booty cannot be readily torn, it is often buried and left until it begins to rot. In connection with their way of feeding, we should notice seveial peculiarities of structure ; the nostrils are at the upper end of the snout, and the eyes and ears are also near the upper surface, so that the Crocodilians can breathe, see, and hear, while the body is alto- gether immersed except the upper surface of the head ; the nostrils can be closed by valves, and the eyes by transparent third eyelids, and the ears by movable flaps, so that the head can be comfortably im- mersed ; a flat tongue is fixed to the floor of the mouth, and the cavity of the mouth is bounded behind by two soft transverse mem- branes, which, meeting when the reptile is drowning its prey, pre- vent water rushing down the gullet; the posterior opening of the nostrils is situated at the very back of the mouth, and when the booty is being drowned, the Crocodilian keeps the tip of its snout above water, the glottis is pushed forward to meet the posterior nares, a complete channel for the passage of air is thus established, and respiration can go on un- impeded. For their shore work the Cr
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Keywords: ., bookauthorth, bookcentury1800, bookdecade1890, booksubjectzoology
