The lemurs, or half-apes, are a large group of small tree-dwelling animals that paleontology shows were in early Tertiary times much more closely connected with monkeys than they are now; and it also shows that in a former age their ancestors were scattered all over the temperate parts of the globe; this assists us to account for the strange distribution of the remnants that now live—a part of them in the Malayan archipelago and a part in central Africa and Madagascar, in which island, indeed, lemurs abound more than elsewhere, owing largely, no doubt, to the scarcity of enemies. They differ from monkeys in having elongated jaws, giving a foxlike aspect to the face, in the woolliness of the coat (as a rule), and in their nocturnal habits and weird cries that have been the source of many curious superstitions and a reverence that no monkey ever inspired.

The typical lemurs have rounded heads, doglike muzzles, and a soft, thick, woolly fur of various colors that is usually extended to form a long, bushy tail; and the largest of them, the "babakoto" of eastern Africa, is as big as a cat, and makes the woods ring at night with doleful howls. They hide in holes in trees or in leafy nests during the day, and at night wander about in trees, or on the rocks of the mountains they frequent, in search of insects and sleeping birds and their eggs, etc. All the lemurs proper, and their relatives, the endrinas, belong to Madagascar. On the mainland a somewhat different race, the galagos, abound throughout central Africa, and are renowned for their leaping powers, general activity, and willingness to eat anything they can catch or find ripe in the way of sweet fruit. They are interesting as pets. The "slow lemurs" of the Malayan islands, on the other hand, are noted for their sleepiness, moving about the trees with such slothlike sluggishness and caution that it is a wonder they ever capture enough food to keep alive. They are regarded with great fear by the natives, not because they are more harmful than the other lemurs, which are also dreaded, but because of strange supernatural powers attributed to them. These ideas are older than our science, for the name, Lemures, given them means "ghosts."

A remarkable thing about the Primates is that they show, even in man himself, many structural traits recalling the anatomy of that remote source of so many mammalian branches, the creodonts; and the lemurs seem to stand between the Insectivora and the Primates, and are certainly the most ancient part of the latter order, with many affinities to the former. In a similar way they are connected with the monkeys and apes by the marmosets. A very suggestive fact is that the scattered distribution of modern lemurs much resembles that of the comparatively few existing insectivores, especially as to Madagascar, which was united with the continent of Africa during the earlier half of the Tertiary era.