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Show 390 MR. G. E. DOBSON ON T H E [Mar. 1, The following points in the osteology of this very remarkable form are especially worthy of notice1 s- The vertebral column is made up of 7 cervical, 15 dorsal, 6 lumbar, 7 sacro-coccygeal, and 23 caudal vertebra?. All the spinous processes, from the axis backwards to the last sacro-coccygeal vertebra, are well developed; that of the axis is enormous, flattened laterally, and antero-posteriorly expanded ; the second dorsal spine is greatly elongated ; the ten anterior dorsal spines are narrowed towards their extremities; the succeeding spines have their extremities progressively antero-posteriorly expanded and laterally flattened, merging into the shape of the lumbar spines, which are nearly as broad at their apices as at their bases. The four anterior cervical vertebrae develop spines (hypapophyses) from the centre of the ventral surface of the body of each, that of the axis being most prominent; the inferior lamellae of the transverse processes of the sixth cervical vertebra are enormously expanded antero-posteriorly, like the spine of the axis; inferior lamellae are also developed in the fifth, fourth, and third cervical vertebrae, but they are very much smaller. The first lumbar vertebra develops a small postero-externally directed transverse process; the remaining five vertebrae have long antero-externally directed falciform transverse processes many times larger and quite differently shaped ; these are succeeded by seven sacro-coccygeal vertebrae, whereof the first two are articulated with the iliac bones. The first caudal vertebra is distinguished, not only by the absence of spinous and articular processes, but also by the want of the chevron bones, which are attached to all the succeeding vertebrae except the terminal two or three : these bones are bifid, and consist of a pair of cylindrical splint-like bones attached by the middle, one on each side, to the infero-lateral surface of the body of each vertebra at its posterior margin, so that half of each bone projects horizontally backwards over the succeeding vertebra; the metapophyses and transverse processes of most of the caudal vertebrae are well developed, and diminish in length progressively backwards. There are fifteen pairs of ribs ; and the thorax is very capacious. Sternum narrow, not keeled; the mesosternum consists of five segments; the xiphisternum is remarkably long and spatulate, terminating in an expanded cartilage, and very like that in Sori-cidae. The pelvic opening is remarkably long and narrow, its width between the acetabula being but one ninth its long diameter ; the symphysis pubis extremely weak, the conjoined rami of the pubis and ischium forming an angular projection, which merely touches the corresponding projection of the opposite side. Humerus well developed, with a supracondylar foramen and a large supratrochlear perforation. Carpus of seven bones, no os centrale; the scaphoid and lunar bones are evidently separate in the 1 In M r . Mivart's paper " O n the Osteology of the Insectivora " (Journ. Anat. Phys. i. pp. 281-312), owing to want of material, the author has touched but cursorily (with the exception of the skull) on the skeleton of this species. |