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Show 718 DR. C I. FORSYTH MAJOR ON THE [June 1, ment than with the molars of Cercopithecidae, which Winge himself declares to be anything but primitive l. As the same author considers the Muridae to be a terminal group-and in this I certainly agree with h i m - I cannot see how we would have to explain the sudden appearance in them of a primitive molar form (that of Cricetus, according to Winge). All the other " Cricetlnl," in their more complicated molars, come nearer to the " Anomalurldce " than does Cricetus. Pseudosclurus and Scluroldes are considered by Winge himself to be the most primitive amongst Anomalurldce. N o w the mesial "transverse ridge" is present in Scluroldes as well as in Trechomys, &c, although in the molars of the former it does not reach so far inwards (in upper molars) or outwards (in lower molars) as it does in Trechomys2. Summary. The Malagasy Muriclce have, by common accord, been placed amongst the " Crlcetlnce " ( " Slgmodontlnce " ) ; this is true in a general sense, at least wdth regard to the great majority of them. In the foregoing pages 1 have tried to define more precisely their position, as well as their relationships with Muriclce from other regions. Although the present paper deals essentially only with one genus, and though it will be necessary for m e to take the Malagasy Eodents (forming, as I consider, a special subfamily, the Nesomylnce) up again as a whole, when all the forms wdl have been fully worked out, I could not, for comparison's sake, avoid anticipating somewhat the future publication, by throwing side-glances on some of the other genera. The Malagasy Rodents have to be considered as the lowest of the Muriclce-lower even than the Miocene members of the family, so far as these are known,-because in cranial and dental characters they approach more than any other Muridce such more primitive groups of Eodentia as the Dlpodldce and Winge's Anomalurldce. These characters are : large infraorbital foramen -well-developed jugale-absence of advanced hypselodontism- intermediate cusps of molars less reduced than in Hesperomyince and in Old World Crlcetlnce, and external cusps (of upper molars) less reduced than in the Murlnce-greater agreement in pattern and size of m. 1 and m. 2 than in other Muriclce; very often all three molars agree with each other. If I had to regret that in m y excavations I came upon but scanty remains of extinct fossil Mammalia, I have had some compensation by these living fossds. Were any justification necessary for having divided my time between neontological and palseonto-logical exploration, this result would amply justify m y proceeding. 1 •' Jordfundne og nulevende Aber (Primates) fra Lagoa Santa, &c.,' Kjobenhavn, 1895 ("EMuseo Lundii"), p. 40. "Hvis Simiinernes Kindtaender vare fremkomne af Tcender saa lidt oprindelig som hos Cercopitheciner . . (The italics are mine.) 2 The comparison of the molars of Sciuroides with those of Pseudosciurus shows that the outer termination (in upper molars) of this " transverse ridge " is nothing but the ancient outer cusp, 2, of Pseudosciurus. |