Miscellaneous. 141 mens, amoug which are two exhibiting the casts of both valves in connexion. It then immediately became evident that several sepa-rate dorsal valves in our collection belonged to the same species. I have therefore now abundant material to illustrate the species, which I shall do soon, but in the mean time propose to notice its leading characters briefly. The ventral valve, in young specimens, is somewhat straight along the median line, but becomes more and more arched as the size increases. It is ovate, rounded in front, widest a little in ad-vance of the mid-length, thence tapering with nearly straight sides to the beak, which is narrowly rounded, almost acute. In the sub-stance of the shell there are two large tubes, which extend from about the mid-length to the beak. These are joined in the beak by two others, one on each side. All of these tubes are open anteriorly, but closed at their terminations in the beak. The area is large, concave, and transversely striated. The dorsal valve is much shorter than the ventral, more convex, and has its beak very strongly in-curved ; it has two tubes, which extend nearly to the apex of the beak. The shell is marked with coarse concentric accretion-ridges of growth. Length of the largest specimen 3| inches, width 3 inches. The above is sufficient to show that this species is quite distinct from T. fjrandis. If a section were to be made across the beak of a perfect shell of T. acuminata, it would show four perforations arranged in a curve, exactly as in the similar section of the Swedish species figured by Dr. Lindstrom. But if the beak of T. grandis were to be cut across, it would show only two orifices, and they would be the homologues of the two lateral perforations in the sec-tion of T. acuminata, because in T. (jrandis the two central tubes do not extend into the beak, but terminate before they reach it.— Silliman^s American Journal, June 1871. On the Skull of the Madoqua (Neotragus Saltianus) //-om Abyssinia, By Dr. J. E. Gray, F.R.S. &c. The British Museum has just received the skuU of a female Neotragus Saltianus from Abyssinia. It is peculiar for being short and broad, with orbits very prominent and the nose much com-pressed ; suborbital fissure small, triangular ; concavity in front of the orbit very large, deej) behind ; the nose-hole very large, more than half the length of the nose ; the intermaxillary bones very long and slender, slightly dilated and expanded outward in front, much broader and truncated behind ; the nasal bones very short, broad, as broad as long, deeply notched on each side of the margin. Lower jaw very slender, elongate, straight, with a weK-produced hinder angle. The chin compressed, keeled. In the size of the nose-hole it is most allied to the genus Pro-capra, and in some respects to Saiga.