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Show 1897.] MALAGASY GENUS BRACHYUROMYS. 697 two; the third upper one slightly triangular. The pattern presented by the uniting of the three enamel-lobes is as follows in moderately worn teeth. In the two anterior npp6i* molars :-• (1) an anterior enamel loop, open on the inner side and running obliquely across the crown, close up to the outer enamel margin of the tooth; (2) a posterior enamel islet, smaller in transverse extent than the anterior loop and almost parallel to it. In the last upper molar the anterior loop is shut out very soon from the inner side, so that this tooth presents two obliquely transverse enamel islets, with sometimes a third, smaller one, behind. In moderately worn lower molars the shorter anterior loop opens on the inner, the longer posterior loop on the outer side, the latter remaining open for a longer time than the former. Dimensions iu millimetres, those of the first two taken in the flesh :- Skin Skin Spirit-specimen (M.429),o*. (M.500)>CJ. (M. 18l),juu. Type. Length of head and body 165 1G2 c. 110 „ tail 99 89 73 „ manus 15 16 16 pes 34 52 27 ear 24 24 17 Dimensions, in millimetres, of the skull (M. 719, 3):-basal length 32*5 ; length of nasals in middle line 13-5; length of frontals in m. 1. 13*5 ; length of parietals in m. 1. 6-3; interorbital breadth at narrowest 4*7; length of upper molar series 8*5 ; length of lower series 8-5; length of interparietal in middle line 5*2; breadth of skull between zygomatic arches 23-5. Loc. Ampitambe Forest, Betsimisaraka country (on the border of N.E. Betsileo), 6 hours S.E. of Eandriana.-Ambohimitombo Forest, Tanala country. Native names voalavoanala (I. e. forest rat); ramlrohltra (meaning probably : who goes in company, gregarious). Fossil in the lower deposits of the Children's Cave (Sirabe). 2. BRACHYUROMYS BETSILEOENSIS. (Plate XXXVII. fig. 1 and Plate X X X I X . figs. 7, 8.) Nesomys betsileoensis, Bartlett (P. Z. S. London, 1879, p. 770). Resembling B. ramlrohltra in outer appearance, but smaller. Tbe brown of the upper parts of the previous species gives place here to fawn, which, together with the black hairs, gives to the upper part of the fur almost an olivaceous colour. Skull resembling that of B. ramlrohltra, but parietal crests nearly parallel; interparietal longer in transverse, shorter in longitudinal diameter. Molar teeth absolutely, as well as comparatively, smaller than in B. ramlrohltra, though large as compared to Muridae in general. Third upper molar small. Enamel loops of all the molars slightly less oblique than in the |