BATS are entirely separated from all other mammals by their ability to fly. This action is made possible by what is really an enormous lengthening of what corresponds to the four outer fingers, which are covered by a delicate and sensitive skin or membrane. All bats come out only at dusk or in the night; some of them feed on flesh, others on fruit. The senses of touch and hearing are exceedingly acute and at night time they can see quite well. During the day they hang, head downwards, in their chosen retreats, but at night they are very active, though their flight is not so rapid as that of birds. The largest of them all are the fruit bats, some of which are known as flying foxes. In all, about seventy species of them are known, some of them measuring so much as four feet across the wing tips.
There are nearly twenty species of British bats, some quite common. They usually sleep during the winter and put on an extra quantity of fat before doing so. Some families possess very curiously shaped growths on the nose, and the ears are enormously large in proportion to their total size. The so-called vampire bats are confined to the New World. None of them are more than about two feet across and of only a few of them can it be said that they can suck the blood of sleeping men or animals. There seems little doubt however that in some cases they do.
A long-descended order are the insect-eaters, in many respects similar to the rodents but differing from them in dentition. They are mostly small, nocturnal animals, living underground, and in temperate climates usually sleeping through the winter. The order includes about one hundred and fifty species, of which about half are shrew-mice, while moles of many species, hedgehogs, musk-rats, etc., account for most of the others.
The last and highest order, with which man himself is closely associated, is called the Primates. In the first group
are what are known as the Lemuroids, about fifty species in all, mostly found in the island of Madagascar. Some of these animals are very unusual in appearance, as for example the curious little aye-aye, which is rather like a squirrel with a hairy body and bushy tail. Some of its fingers have long claws and others short ones. Another member of this family is the spectral tarsier of Malay, which has enormous eyes and a long tail. The small bones of the ankle (or tarsus) are greatly lengthened. The Maholi galago, or ‘bush baby ‘may also be mentioned, a gentle little creature easily made into a pet. More nearly approaching the monkeys are the true lemurs, though their foxy appearance and large nocturnal eyes rather disguise the relationship. The ring-tailed lemur with his long tail is well known, while the largest of the group is the black and white ruffed lemur.