Page:Popular Science Monthly Volume 34.djvu/347

Rh does not depend on mere change of attitude, but also on the unusually lithe and mobile nature of the entire spinal column and ribs, furnished as these are with an abundance of cartilaginous material and fibro-elastic ligaments."

The Otaria has generally thirty-six teeth, with canines and incisors of enormous size, so that when they close upon each other "anything that may happen to come between them is held as in a vise," and small molars, so solid that sailors have sometimes mistaken them for flints. According to Mr. J, W. Clark, of Cambridge, whose "Davis Lecture" on these animals at the London Zoölogical Gardens condenses a mass of information about them, "The Otaria, having caught its prey, holds it in its mouth by means of its powerful canines and incisors, and, raising its head, swallows it whole. When it has caught a fish too large to be thus disposed of, it has been seen to give its head a sudden twist, so as to break off a portion, which it swallows rapidly. It then dives into the water, picks up the other portion, and repeats the tearing process until the last fragment is devoured. Their food consists of fish, mollusca, crabs, and sea-fowl, especially penguins, which they catch in a most ingenious way. They lie motionless in the water, with only a small portion of their nose above the surface. This attracts the attention of the bird, which mistakes it for something eatable, and, approaching to catch it, falls a prey to the craft of its adversary." They have also the habit of swallowing pebbles, of which more than twenty pounds, some of them weighing half a pound, have been taken from one animal. The sailors say that this is for ballast, and a story is told of a female seal that was seen teaching her cub to swallow the pebbles; while another story, by an officer of the British navy, is of a sea-lion that was seen "discharging ballast."

The breeding habits of the sea-lions, as they are described by several authors, among them Mr. J. A. Allen, in the "Harvard Bulletin," and Mr. H. W. Elliott, in his report on the Pribylov group of islands, are extremely curious. They frequent solitary islands, away from inhabited coasts, in large numbers, and are supposed generally to return to the same place, or near it, year after year. Here they occupy the spaces between high-water mark and the foot of the cliffs—to which the sailors have given the name of "rookeries"—using the beach as a playground for the pups, and fixing their sleeping-places on the tops of the cliffs.

Only the old males or "married seals," and the full-grown females or "mothers," are allowed upon the rookeries. The youngseals—the young males are called "bachelors"—are left to swim about in the water, or are allowed to retire behind the rookeries to the uplands back of the grounds that the old seals have appropriated to themselves. Communication between their upland