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Show 1899.] ON THE SKULLS OF SOME MALAGASY LEMURS. 987 central line; on either side of the black stripes were pale fawn stripes ; outside these again were black stripes. The general body-colour was soft greyish brown. The fur was very soft, like that of Malacothrix, so that the general effect of this colouring was particularly pleasing. The tail was barely so long as the head and body, and was thickly covered with short hairs. Mr. E. E. Holding exhibited, on behalf of Mr. William Pierpoint, a series of the horns of the Siberian Eoebuck (Capreolus pygargus) brought from the Gulf of the Obi, Siberia, and pointed out some remarkable variations in the form and size usually characteristic of the horns of this species. Mr. Holding also exhibited a pair of the horns of the Altai Deer (Cervus eustephanus) from the same district, which were mainly interesting on account of the absence of the third tine on both horns-a somewhat unusual case, as the third tine in this group of Deer is the most persistent, the " bez" tine being usually arrested. A pair of horns, probably of the same species, also showing the third tine absent, had been shown by M r . H . J. Elwes at a recent meeting of the Linnean Society and figured in the Journal of that Society for 1899 (Zool. vol. xxvii. p. 32). Dr. Forsyth Major, F.Z.S., exhibited several skulls of foetal Malagasy Lemurs, partly collected by himself and partly lent to him by the Hon. Walter Bothschild, M.P., and Prof. Charles Stewart, P.E.S., and made the following remarks :- All the Malagasy Lemurs, Chiromys included, exhibit a remarkable peculiarity of their tympanic bulla, the annulus tympanicus taking no part whatever in its conformation. This condition is unique amongst the Mammals, if we except the Insectivorous form Tupaia (Winge), to which I a m able to add the nearly related genus Ptilocercus. To decide the question whether this is a primitive condition in Malagasy Lemurs, w e have in the first place to investigate how the bulla is developed. In the youngest stage available to m e for examination, the foetus of a Chiromys, there is no trace of an osseous bulla; the completely ossified annulus lies almost horizontally underneath the periotic. In a second stage (Lepidolemur) ossification begins to be developed from the lower sharp margin of the periotic, which adjoins the annulus. In a third stage (Lepidolemur) this outgrowth appears increased, and has a shell-like shape, with the concavity turned outward; the annulus is gradually being uplifted by it. In a fourth stage (Lemur rubriventer) the shell-like ossification is still more increased, and begins to cover the median part of the annulus ; and this state of things is still more increased in the fifth (Lepidolemur) and sixth stage (Avahis laniger), with the result that first the median part, and eventually the remainder of the annulus becomes invisible when viewed from below, being shut by the periotic |