The female kangaroo, however, is not nearly so well able to defend herself, and sometimes she has been known, when chased by hounds, to lie down and die simply from fear. But sometimes she escapes by taking a sudden leap sideways into thick bushes, lying perfectly still until her pursuers have rushed past her, and then making off in the opposite direction. As the mother kangaroo hops about, the head of her little one, or "joey," as it is called, may often be seen poking out of her pouch. And she is so clever that if an enemy should appear when the "joey" is playing on the ground or feeding, she will snatch it up and put it into her pouch even while she is hopping away, without pausing for a moment in her retreat. [Illustration: TYPES OF MARSUPIALS 1. Australian Sugar Squirrel. 2. American Opossum. 3. Australian Echidna. 4. Australian Great Kangaroo. 5. Tasmanian Devil.] A JOYOUS MEETING Kangaroos are very affectionate animals, and a touching story is told of a couple which lived together in captivity. They became the very best of friends, but when they were sent from Australia to Philadelphia, they had to travel by different ships. As soon as they were separated, they became miserable, moping in their cages, refusing to take food, and calling for each other all day long. "Jack," as the male was called, reached Philadelphia first, and for a whole week seemed to be constantly on the watch to see if "Flora," his mate, was coming. At last she arrived, and both animals at once became madly excited, leaping in their cages so wildly that at last they were put together, to prevent them from injuring themselves against the bars. Then they cuddled up against one another, licked each other with their tongues, and seemed so overjoyed to meet that the keeper promised that they should never be parted again. VARIOUS SPECIES OF KANGAROOS Kangaroos generally live in droves, sometimes consisting of only a few animals, sometimes of as many as a hundred and fifty, or even more. But a "boomer" often lives during the greater part of the year quite alone, like a "rogue" elephant. There are at least twenty-three different kinds of kangaroos, the smaller ones being generally known as wallabies. And these are again divided into large wallabies and small wallabies. The large wallabies are also called brush-kangaroos because they live in the thick brushy jungle, called the bush, which occupies so large a part of the Australian continent. The biggest of them is really quite a large animal, for when fully grown it is six feet long, from the tip of the muzzle to the end of the tail. Some of the small wallabies, however, are very small, several of them being no bigger than rabbits.