The age of this Howling Lemur, estimated either geologically or by years, cannot be of very great antiquity. Its remains were found associated with those of the giant Moa-like bird, the Æpyornis, of Tortoises and Hippopotami, all now extinct, and of Crocodiles still living in the interior lakes of the island. Some of these animals were certainly contemporaneous with the now vanished Dodo and the large flightless Rail (Aphanapteryx), both of which were seen alive by Europeans little more than two centuries ago, and it is not improbable that Megaladapis may have been living in the Madagascar forests at the same period.
FAMILY LEMURIDÆ (anteà, p. [22]).
In this family, and in its sub-family Lemurinæ (because of its affinities with Hapalemur), has to be included a large extinct species from Nossi Vey, in North-west Madagascar. Its fossil remains were recently described (P. Z. S., 1893, p. 532), but not named by Dr. Forsyth Major. They will prove, he believes, when more fully known, to be the type of a new genus. At present, however, owing to their incomplete state, it is not possible to describe the species fully. "The Lemuroid nature of the specimen is at once demonstrated by the great elevation and downward bending of the post-orbital processes ... showing that the osseous ring of the orbit was complete." Unusual for a Lemuroid is the very strong post-orbital constriction of the frontals, a character, however, seen in Adapis, an Eocene European form, and in Hapalemur. With the latter it agrees in the voluminous cranial and very short facial portion, and the "cuttingly sharp" inferior margin of its post-orbital process. Seen from the side, this fossil cranium is almost vertically truncated behind, as in the skull of Alouatta. The region between the eyes is vaulted by underlying air-chambers.
FAMILY ANAPTOMORPHIDÆ.
This family includes certain fossil forms of Lower Eocene age from the phosphatic deposits of Quercy in France, the Wasatch strata of Wyoming, and the Puerco beds in New Mexico. Their dental formula is the same as that of existing Lemurs, namely I2(2-1), C1(1-0), P(2-3)(2-3), M33. In some of the genera there is a tendency to develop, as Cope has pointed out, large cutting teeth in the position of incisors, "thus approaching the Aye-Aye." The posterior pre-molars are more simple than the anterior true molar, a character which indicates some relationship to the Mouse-Lemurs (Chirogale). The mastoidal or posterior portion of the ear-capsules, and the neighbouring squamosal region of the cranium are swollen, as among the Galagos.
GENUS MICROCHÆRUS.
Microchærus, Wood, Lond. Geol. Journ., i., p. 5 (1846).
Heterohyus, Gerv., Zool. et Pal. Fr., p. 202, pl. 35, fig. 14.
Necrolemur, Filhol, C. R., lxxxvii., p. 1112 (1873); id. Ann. Sc. Geol., viii., p. 55, pl. iv., figs. 213-217 (1877).
This genus is distinguished from all other Lemurs by "the angle of the mandible being produced into a large hook-like flange." (Flower and Lydekker.) The orbits are large, indicating a nocturnal animal; the inter-orbital space is wide, and distinguishes it from Loris. The dental formula is I21, C11, P33, M33. The canine teeth are not prominent; the anterior lower pre-molar is only slightly developed; a gap separates the anterior and the median upper pre-molars.