are employed. The upper incisor is greatly enlarged, and of somewhat triangular shape (Fig. 323); the canine, although smaller than the incisor, is large and sharp; but the cheek-teeth are very small, with laterally compressed crowns rising but slightly above the level of the gum, their longitudinally disposed cutting-edges being continuous with the base of the canine and with each other. The lower incisors are small, bifid, and separated from the canine,

with a space in front.

The lower cheek-teeth are narrow, like those in the upper jaw, but the anterior tooth is slightly larger than the others, and separated by a small space from the canine. Behind the lower incisors the jaw is deeply hollowed out to receive the extremities of the large upper incisors. The exceedingly narrow œsophagus opens at

right angles into the slender, intestine-like stomach, which almost immediately terminates on the right, without a distinct pylorus, in the duodenum, but on the left forms a greatly elongated fundus, bent and folded upon itself, appearing at first sight like part of the intestines. This cardiac extremity of the stomach is, for a short distance to the left of the entrance of the oesophagus, still very narrow, but soon increases in size, till near its termination it attains a diameter quite three times that of the short pyloric portion. The length of this cardiac diverticulum of the stomach appears to vary from 2 to 6 inches, the size in each specimen probably depending on the amount of food obtained by the animal before it was captured.

Diphylla.-A small true molar in each jaw, and a rudimentary calcar. The single species D. ecaudata inhabits Brazil, and appears to be much less abundant than Desmodus rufus, from which, in addition to the characters already mentioned, it is distinguished by its slightly smaller size, the absence of a groove in the front of the lower lip, the non-development of the interfemoral membrane in the centre, and the peculiar form of the lower incisors, which are much expanded in the direction of the jaws and pectinated, forming a semicircular row touching each other, the outer pair being wider than the inner ones, and having six notches, the inner pair having only three notches.

Fossil Phyllostomatida.-Remains of Vampyrus spectrum, as well as of several species of Phyllostoma or closely allied types, are found

1 Spix, Sim. et Vesp. Brasil, p. 68 (1823).

in the cavern-deposits of Brazil. The mandible of a large Bat from the Upper Eocene Phosphorites of Central France, described as Necromantis, has been referred to this family-a determination which, if confirmed, will be of great interest from a distributional point of view.

Bibliography of Chiroptera.-G. E. Dobson, Catalogue of the Chiroptera in the Collection of the British Museum, 1878, including descriptions of all the species of Bats then known; subsequent papers by the same author in Rep. Brit. Assoc., Proc. Zool. Soc., Ann. Mag. Nat. Hist., and Bull. Soc. Zool. de France; by Peters in Monatsb. Akad. Wiss. Berlin; by O. Thomas in Ann. Mag. Nat. Hist., Proc. Zool. Soc., and Ann. Mus. Genova; and by J. Scully in Ann. Mag. Nat. Hist. and Journ. As. Soc. Bengal; H. A. Robin, Recherches Anatomiques sur les Mammifères de l'Ordre des Chiroptères, Paris, 1881; W. T. Blanford, "Notes on Indian Chiroptera," Journ. As. Soc. Bengal, vol. lviii. (1888). See also papers by Jentink, Bocage, and others.

1

CHAPTER XIV

THE ORDER PRIMATES

THIS order in the system of Linnæus includes Man, the Monkeys, the Lemurs, and the Bats. By common consent of all zoologists the last-named animals have been removed into a distinct order; but with regard to the association of the others there has been, and still is, much difference of opinion.

That all the Monkeys, from the highest Anthropoid Apes to the lowest Marmosets, form a natural and tolerably homogeneous group seems never to have been questioned; but whether the Lemurs on the one hand and Man on the other should be united with them in the same order are points of controversy. If, in accordance with the traditional views of zoologists, the former are still considered to be members of this order, they must form a suborder apart from all the others, with which they have really very little in common except the opposable hallux of the hind foot, a character also met with in the Opossums, and which is therefore of very secondary importance.1

Using the term Primates in this wider sense it is not easy to give any precise definition of the order. The dentition is diphyodont and heterodont; the number of incisors being very generally , and that of the molars, with the exception of the Hapalide, being. The cheek-teeth are adapted for grinding, the molars being more complex than the premolars, and usually having four main tubercles, which may be either subconical or more or less compressed. The orbit is invariably surrounded by a ring of bone;

1 For the arguments in favour of placing the Lemurs in a separate order see Milne-Edwards, "Observations sur quelques points de l'embryologie des Lemuriens et sur les affinités zoologiques de ces animaux," in the Ann. des Sciences Nat. October 1871; and P. Gervais, "Encephale des Lemures," in Journ. de Zoologie, tom. i. p. 7. For those for retaining them among the Primates, see Mivart, "On Lepilemur and Chirogaleus, and on the Zoological Rank of the Lemuroidea," in Proc. Zool. Soc. 1873, p. 484.

the clavicles are well developed; and the radius and ulna are never united. The scaphoid and lunar of the carpus, and commonly also the centrale, remain distinct from one another. There are usually five digits furnished with well-developed nails in both the manus and the pes; but the pollex may be rudimentary or wanting. The hallux, except in Man, is opposable to the other digits, and has a flat nail (absent in Simia); and the pollex, when present, is usually also more or less opposable.

The terminal phalanges of

the digits are flattened (except in the second digit of the pes of the Lemuroidea), and not cleft at their extremities. The fingers and toes generally do not taper towards their extremities, but (except in Chiromys) are dilated, flattened, and rounded at their tips. The humerus has no entepicondylar foramen, nor the femur a third trochanter. In the alimentary canal (Fig. 324) the stomach is generally simple, although sacculated in the subfamily Semnopithecina of the Cercopithecida; and there is always a cæcum, which is generally of large size. The placenta may be either non-deciduous, or discoidal and deciduous. There are always two mammæ in the pectoral region, except in Chiromys; and the testes descend into a scrotum.

FIG. 324.-Alimentary canal of Galago, the greater part of the small

intestine being omitted. d, duo

denum; i, ileum; cm, cæcum; r,

rectum.

The Lemuroidea are decidedly low in the scale of organisation, their placentation being of a lower type than that of the Insectivora; and all the Primates retain generalised features in their pentadactylate limbs and more or less bunodont cheek-teeth. In respect to cerebral characters and other features the higher representatives of the order have, however, acquired a specialisation clearly indicating their right to occupy the highest position in the animal kingdom. So far as the available material admits of forming an opinion, fossil forms appear to indicate an intimate connection between the Lemuroidea and Insectivora, so that in some cases it is almost impossible to determine whether an extinct type should be referred to the former or to the latter group. It is noteworthy that while in all existing Primates the upper molars are of a quadrituberculate type, in the extinct Lemuroid genus Anaptomorphus they are trituberculate.

Suborder LEMUROIDEA.

The Latin term Lemur was applied by Linnæus to the typical representatives of the present group of Primates, having been suggested by the nocturnal habits and strange ghost-like appearance of some of its members. As these animals had previously no vernacular appellation in English, this name has been generally adopted, and is now completely anglicised, making "Lemurs" in the plural. The French call them Makis, and the Germans Halbaffen, in allusion to their forming a transition from monkeys to ordinary quadrupeds. For the same reason they are called Prosimi by some systematic writers. When the name was bestowed by Linnæus only five species were known, of which one, L. volans, Linn. (Galeopithecus volans of modern writers), is now removed by common consent from the group. Notwithstanding the discovery of many new and curious forms, the Lemurs remain a very natural and circumscribed division of the animal kingdom, though no longer considered a single genus, but divided up into many genera and even families.

The existing species are not numerous, and do not diverge widely in their organisation or habits, being all of small or moderate size, all adapted to an arboreal life, climbing with ease, and, as they find their living, which consists of fruits, leaves, birds' eggs, small birds, reptiles, and insects, among the branches of the trees, they rarely have occasion to descend to the ground. None are aquatic, and none burrow in the earth. Many of the species, although by no means all, are nocturnal in their habits, spending the day in sleeping in holes, or rolled up in a ball, perched on a horizontal branch, or in the fork of a tree, and seeking their food by night. Their geographical distribution is very peculiar; by far the larger proportion of species, including all those to which the term "Lemur " is now especially restricted, being exclusively inhabitants of Madagascar, where they are so abundant and widely distributed that it is said by M. Grandidier, who has contributed more than any other traveller to enrich our knowledge of the structure and manners of these animals, that there is not a little wood in the whole island in which some of them cannot be found. From Madagascar as a centre a few species less typical in character extend through the African continent westward as far as Senegambia, and others are found in the Oriental region as far east as the Philippine Islands and Celebes.

The following are the essential characters by which the suborder as a whole is distinguished from the Anthropoidea. Skull with the orbit opening freely into the temporal fossa beneath the postorbital bar (except in Tarsius); and the lachrymal foramen