Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/464

 444 LEMUR pressed claws, like that of the second toe in the Lcmurinss and the second and third in the Tarsiidse. Tail long and bushy. General colour dark brown, the outer fur being long and rather loose, with a woolly undercoat. Mammae two, inguinal in position. It is a native of Madagascar, where it was discovered by Sonnerat in 1780. The specimen brought to Paris by that traveller was the only one known until 1860. Since then many others have been obtained, and one has lived for several years in the gardens of the Zoological Society of London. Like so many of the lemurs, it is completely nocturnal in its habits, living either alone or in pairs, chiefly in the bamboo forests. Observations upon captive specimens have led to the conclusion that it feeds principally on succulent juices, YIG. 6. Skull of Aye-aye (Chiromys madagascariensis). x f. Mus. Roy. Coll. Surgeons. especially of the sugar cane, which it obtains by tearing open the hard woody circumference of the stalk with its strong incisor teeth. It is said also to devour certain species of wood-boring cater pillars, which it obtains by first cutting down with its teeth upon their burrows, and then picking them out of their retreat with the claw of its attenuated middle finger. It constructs large ball-like nests of dried leaves, lodged in a fork of the branches of a large tree, and with the opening on one side. The resemblance of its teeth to those so characteristic of the Rodcntia caused it to be placed for merly in that order, and it was only when its anatomical characters were fully known that its true affinities with the lemurs became apparent. 1 Extinct Lemuroidea. The disputed zoological position of the lemurs, and the great importance which has been attached to them by those naturalists who regard them as the direct transition between the lower and higher mammals, and survivors of a large group, now almost extinct, through which the higher Primates, including man, must have passed in the progress of their development, make the consideration of their ancient history one of great interest. Until very recently fossil lemurs were quite unknown ; at all events the affinities of certain remains provisionally assigned to the group were much questioned ; but within the last few years the existence of lemuroid animals in Europe during the later Eocene and early Miocene periods has been perfectly established, and remains of a large number of animals attributed, though with less certainty, to the group have been found in beds of corresponding age in North America. In 1862 Kutimeyer described the fragment of a right maxilla and three molars from a sidero- litic deposit (Bohnerz) at Egerkingen, near Soleure, under the name of Ceenopithecus lemuroides, supposing them to belong to an animal partaking of the characters of the American monkeys and the lemurs. The remains were, however, by most other palaeontologists referred to the Ungulata. More recently M. Betille discovered in deposits which were being worked for phosphate of lime at Sainte Neboule de Beduer, department of Lot, France, regarded as of early Miocene age, a nearly complete cranium, and subsequently, at the same place, a portion of a ramus of a mandible of apparently the same species of animal. These were described by M. Delfortrie in the Actes de la Societe Linneenne de Bordeaux for 1872 under the name of 1 R. Owen, &quot; On the Aye-aye,&quot; in Trans. Zool. Soc., vol. v. p. 33, 1862 ; W. Peters, &quot; Ueber die Saugethier-Gattung Chiromys,&quot; in Abhand, KiJnigl. Akad. der Wissenschaften, Berlin, 1865, p. 79. Paleeolemur betillei. The cranium is generally well preserved, but unfortunately the anterior part, containing the incisor and canine teeth, has been broken off. Its affinity to the lemurine animals, especially to the African forms, the Lorisinx and Galayinse, is chiefly shown by the general form of the cranium, the large size and anterior direction of the orbits, the small and narrow muzzle, and the position of the lacrymal foramen outside the anterior edge of the orbit. In size the fossil is intermediate between the potto (Perodicticus potto) and Galago crassicaudatiis. When the specimen came into the hands of M. Gaudry, that experienced and accurate palaeontologist, with the rich treasures of the Paris Museum at hand for comparison, recognized that certain more or less fragmentary remains which had long been in the collection, and had been described from the teeth alone, and generally, though doubtfully referred to the Ungulata, were really nothing more than animals of the same group, and probably even the same species as Palseolemur letillei. These were Adapis /&amp;gt;arme;m s, Cuvier, from the Paris gypsum, described and figured in the Ossemens fossiles, Aphelo- therium duvernoyi, Gervais, from the same beds, and other specimens from Barthelemy, near Apt. This result was fully acquiesced in by Gervais, who also added Csenopithecus lemuroides, Riitimeyer, to the synonyms of the animal, which henceforth must be called Ada2nsj)arisiemis, as that was the name first assigned to it. M. Delfortrie s announcement of a fossil lemur from the south of France was soon followed by that of another species by M. H. Filhol, named Necrolemur antiquus (Comptes Kendus, 1873, torn. Ixxvii. p. 1111), which was afterwards more fully described and figured (Annales des Sciences Geologiques, torn. v. No. 4, 1874, and Recherches sur les Phosphorites du Quercy, 1876), and a second species of Adapis, of considerably larger size, A. maynus, Filhol, was added to the group ; the latter, of which the skull is upwards of 4 inches in length, resembles M. Delfortrie s in its general characters, but modified much in the way that the skulls of larger animals differ from the smaller ones of the same natural group. The brain-chamber and orbits are relatively smaller, the face larger, the muscular crests more developed, and the constriction between the cerebral and facial portion of the skull more marked. These modifica tions remove the skull in its general characters still further from the existing lemurs so much so that M. Filhol refers it and the other species of Adapis to a distinct and hitherto unknown zoological type, intermediate between the lemurs and the pachyderms, to which he gives the name of Pachylemur. On the other hand he considers the Necro lemur antiquus found at St Antonin, which is a very small species, to be a true lemuroid, more nearly resembling Galago senegalensis than any existing species. Unfortu nately in all these specimens the anterior part of the skull is so much injured that the character and numbers of the incisor teeth cannot be ascertained, a great want in determining the affinities of these animals. And even if the whole of the skulls were found, as long as nothing is known of the limbs, or of any other bones of the skeleton, the determination of their actual zoological position can only be considered as provisional. All the existing lemurs and pachyderms, or ungulates as they are now generally termed, are so essentially different in structure and mode of life that it is difficult to conceive of a transition from one to the other, and therefore any such forms when found will be full of interest. In skull and teeth characters, as far as they are yet known, these ancient lemur-like animals from France do not deviate sufficiently from the existing lemuroids to justify their separation, but it remains to be proved whether they had the opposable hallux and ungui- culate toes of the forms which now inhabit the world,