Ninth thoracic: Metapophyses squared. Transverse process similar to that of eighth thoracic, but equal to centrum in length, little narrowed at base, and directed outward; anterior edge convex, posterior concave; articular facet occupying the posterior half of the distal edge. A very shallow groove proximally.
Newport (male).—First thoracic: Neural spine a little curved backward and rounded at tip; much higher than length of arch and centrum together. Articular facets as in Barnegat skeleton.
Seventh thoracic: Metapophyses similar in shape to those of Barnegat skeleton but with a very distinct facet on side of arch, terminating a process about as long as the greatest diameter of the facet; surface of facet rugose. Below this process, on side of centrum, a very large, oval, sessile facet, reaching forward nearly to the anterior face of the centrum and upward to its superior edge. A very low, small swelling on the posterior superior edge of centrum, probably indicating the point of attachment of a cartilage connecting the head of the eighth rib. Neural spine expanded at free end, and superior margin rounded.
Eighth thoracic: Metapophyses similar to those of Barnegat skeleton. A distinct transverse process nearly as broad as the length of the centrum, oblong or squared, flat, directed somewhat backward, but not upward. Articular facet for rib not occupying whole of free end and only slightly directed backward; anterior margin as in Barnegat skeleton. Neural spine similar to that of seventh thoracic.
Ninth thoracic: Similar to that of Barnegat skeleton, but transverse process longer than centrum and directed a little downward, articular facet occupying less than posterior half of free margin; proximal groove inconspicuous; anterior and posterior margins nearly straight.
Charleston (female, jr.).—The centra of the thoracic, as well as the lumbar, vertebræ in this individual present inferior median keels, and more or less concave sides, which is not the case in the Barnegat and Newport skeletons. This can not be due to immaturity, as in a still younger individual, supposed to represent Ziphius grebnitzkii, the thoracic vertebræ are rounded below. The neural spines of the thoracic vertebræ are much less inclined backward in semijunctus than in the Newport and Barnegat skeletons, but this is doubtless connected with age, as the younger series of vertebræ already mentioned exhibits the peculiarity in a more marked degree. A similar modification dependent upon age appears to affect Hyperöodon, as will be seen by comparing Van Beneden and Gervais’ figures in the Osteography, plate 18.
First thoracic: Similar to that of Newport skeleton, but spine not higher than arch alone. (A little abraded at tip, but probably undeveloped.)
Seventh thoracic: Metapophyses short (abraded), incompletely developed. A distinct facet on side of same on an elongated process, as in Newport skeleton, but no second larger one on side of centrum. No facet on superior margin of centrum either anteriorly or posteriorly.
Eighth thoracic: Transverse process similar to that of Barnegat skeleton, but anterior edge nearly straight; process about one-half as broad as length of centrum. (Indications of immaturity.)