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Show 988 ON SUBFOSSIL MAMMALS FROM MADAGASCAR. [Dec. 19j In the adult (as will be seen by the skull of an adult Lemur rubri-venter which I exhibit) the annulus is represented by a bony ring- the size is scarcely larger than in the youngest stages-which hangs freely in the tympanic cavity, being coalesced with the squamosum only in one part, viz. anteriorly to the stylo-mastoid foramen. Ontogeny thus teaches us that the annulus of the adult is not a secondarily detached part of the bulla. In the second place, I have to state, in connection with the above, the important fact, that in the Tertiary Aclapis the annulus tympanicus is a free ring, independent of the bulla, absolutely as in the Malagasy Lemurs. Besides, in the large development of the bulla and in the conformation of the whole of the basicranium (in the shape and position of foramina &c), Adapis closely resembles the Malagasy Lemurs. So that, far from agreeing with Osborn and Wortman, who place Adapis among the "primitive Anthropoidea," I now see no reason for separating it as a family from Malagasy Lemurs. In the Oriental and Ethiopian Lemurs both the annulus and an outgrowth from the petrosum enter into the composition of the bulla. In a young Nycticebus (which I exhibit) it is to be seen that the median part of the bulla is, as in Malagasy Lemurs, formed from an appendage of the periotic, which becomes co-ossified with the annulus; in the specimen exhibited the suture between them is distinctly visible. The annulus, in its turn, no longer plays the passive part that it does in Malagasy Lemurs, but grows out laterally, so as to form the lateral part of the tympanic cavity, which, however, never reaches the dimensions it has in Malagasy Lemurs. I have not, for the present, sufficient material to follow* the process of development in detad in other Malagasy Lemurs. In the skull of a half-grown Galago, it may be seen that the composition of the bulla is essentially the same as in Nycticebus. Prom the close agreement in cranial characters between the last-named and Loris and Perodicticus, it may be safely argued that in the development of their bulla they also agree with Nycticebus. The same holds good with regard to Tarsius, as shown by a young skull of Tarsius spectrum now exhibited. Dr. Forsyth Major also asked leave to exhibit specimens of two subfossil Mammals from Madagascar, which would be fully described later on; but he preferred not to delay their exhibition, as very soon it would probably be no longer in his power to exhibit them. Dr. Forsyth Major made the following remarks;- This almost complete skull, together with a mandibular ramus, represents a new species of Nesopithecus, which may be called Nesopithecus australis, sp. nov. It is distinguished from N. roberti by its smaller size, by the less steep facial profile, by the position of tbe lachrymal foramen situated on the margin of the orbit, and not inside as in N. roberti, and by the slightly outward direction of the orbits. This beautifully preserved specimen shows that the genus Globilemur founded by m e on the posterior, and Nesopithecus roberti |