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Show 472 DR. J. V. HAAST ON ZIPHIUS NOV^E-ZEALANDI^. [June 6, Thoracic Vertebra. Their number, as before stated, is nine. In this respect the New- Zealand species resembles Hyperodon, which, as far as I am aware, is the only other known Ziphioid Whale having such a small number of thoracic vertebra?. Each vertebra has a spine standing backwards at an angle of 60 degrees to the body of the vertebra. That of the first one is pointed, 6*4 inches high, and 2*05 inches broad at the base. Gradually these spinous processes rise higher and become broader at the same time, that of the 9th or last thoracic vertebra being the highest, 11*62 inches, and 3*46 inches broad at the base. They are all laterally compressed, thinning out at the top to a mere blade. The first two vertebrae possess on both sides of the arch a rounded apophysis, on which the articular extremity for the tubercle is placed. This apophysis gradually enlarges, being laterally compressed and showing one well-marked process pointing upwards and forwards, as well as the articulation for the tubercle for the rib, which is situated more backward. On the seventh vertebra this separation of the apophysis is still more conspicuous, whilst on the eighth vertebra a separation of that apophysis into two distinct portions has taken place, the forward or superior process now appearing as the metapophysis, whilst its lower or posterior portion forms now a lower transverse process, on which the articular surface for the eighth rib is situated, directed obliquely backwards. This lower transverse process is already situated in front, on the body of the vertebra, but on its upper portion. This division is still more conspicuous in the ninth or last thoracic vertebra, where the metapophysis has nearly the same form as that on the first lumbar vertebra, with the exception that its upper surface has a rounder instead of a horizontal edge. The lower transverse process has a more depressed, flattened form; moreover it is situated not only in the centre of the body of the vertebra, but also lower down and nearly on the same level as the same process in the first lumbar vertebra. The bodies of the vertebrae gradually increase in size, the first having an antero-posterior length of 1*65 inch, and the ninth, or last, of 4*1 inches. The inferior surface of the first thoracic vertebra is rough and rounded. The second, third, and a small portion of the anterior part of the fourth have a shallow concave groove, after which on the fourth a median keel appears, which continues to run along the rest, gradually becoming more pronounced. Lumbar Vertebra. The nine thoracic vertebrae are succeeded by eleven lumbar vertebrae, which nearly all possess the same form, attaining larger dimensions as they follow each other, so that the body of the last is the largest-viz. 5*48 inches for the first, and 7*58 inches for the last lumbar vertebra. The spines are of considerable size, the first being 13*25 inches high along its posterior margin ; they then gradually rise to the eighth, which is 15*52 inches high, after which |