Aphelotherium, Gervais, Zool. et Pal. Franç. (1), ii., Exp. 34 (1848-52).
Cænopithecus, Rütim, Denksch. Schw. Ges. Nat., xix., p. 88 (1862).
Notharctus, Leidy, Geol. Surv. Mont., p. 364 (1871).
? Thinolestes, Marsh, Am. Jour. Sci., 1872 (2), p. 205.
? Telmalestes, Marsh, op. cit., p. 206.
"The general form of the cranium," to quote Sir W. Flower, "the large size and anterior direction of the orbits, the small and narrow muzzle ... show its affinity to the Lemurine animals, and especially to the African forms. The whole skull, however, is more depressed than in the slow Lemurs and Galagos; the orbits are smaller, the brain cavity relatively smaller and more constricted behind the orbits, and the muscular ridges more developed."... The lower jaw is deep and stout. The posterior upper pre-molar is very similar to a true molar. "The upper molar teeth are nearly equal in size, and have nearly square crowns, with four distinct cusps, one at each angle, rather obliquely placed"; the hind inner cusp of the posterior molar inconspicuous. The lower molars have two pairs of obliquely placed cusps, connected by transverse ridges, anterior and posterior, with an oblique ridge running forwards and inwards from the outer hind cusp. The hindmost lower pre-molar has an internal cusp; the lower incisors have upright spatulate crowns like those of true Apes.
Several species of this genus have been described. Adapis Parisiensis (with the synonyms of Aphelotherium duvernoyi, Gervais, and Palæolemur betillei, Delfortrie) is one of the best known, and its remains have been found in Upper Eocene strata at Egerkingen, in Switzerland, at Sainte Néboule de Béduer, and in the Paris Gypsum, in France, as well as in England. It "more nearly resembles the Indo-African Lemurs, and not those of the island of Madagascar, or of the extreme east, having no near relationship with the Tarsius, the Aye-Aye, or the Indris, and not much with the true Lemurs." (Flower.) From the Eocene of Switzerland comes A. lemuroides. Adapis magna (Filhol) is larger than the preceding species, has a larger face, and a greater constriction between the cerebral and facial regions of the skull. It has been found in the phosphatic deposits at Raynal, in France. Adapis angustidens (Filhol), from the Quercy Phosphates of France, is distinguished by the structure of its molars, and by the great size of its two anterior pre-molars. A. tenebrosus (Leidy) has a large lower canine. A. minor (Filhol) is an additional species.
GENUS TOMITHERIUM.
Tomitherium, Cope, Vert. Bridg. Eoc. Wyom., p. 2, 1872.
Limnotherium, Marsh, Am. Journ. Sci., 1871, ii., p. 43 (in part).