. Carnegie Institution of Washington publication. vertebrje, and is regarded as the possible attachment of a cartilaginous neural spine. The anterior and posterior zygapophyses and the zygosphene and zygantrum are well developed. There is a low keel on the lower surface which is somewhat broadened at the anterior and posterior ends. On the sides are two well-developed processes for the double-headed ribs; the lower is attached to the centrum and the upper to the neural arch. From this point the dorsal vertebrse are quite similar. The centrum is elongate with the lower surface concave antero-po
. Carnegie Institution of Washington publication. vertebrje, and is regarded as the possible attachment of a cartilaginous neural spine. The anterior and posterior zygapophyses and the zygosphene and zygantrum are well developed. There is a low keel on the lower surface which is somewhat broadened at the anterior and posterior ends. On the sides are two well-developed processes for the double-headed ribs; the lower is attached to the centrum and the upper to the neural arch. From this point the dorsal vertebrse are quite similar. The centrum is elongate with the lower surface concave antero-posteriorly, and in the large specimens nearly flat from side to side near the middle. In smaller speci- mens the lower surface is convex from side to side. There is no trace of a keel on the centrum after the second ver- tebra. The neural spine is heavy and low, with a deep pit, possibly for the attachment of a cartilaginous spine. In the American Museum specimen, No. 4472, the processes for the ribs remain distinct to the twelfth or thirteenth, where they fuse and form a strong transverse process, which is quite elongate, with a broad distal end. The last trace of this lateral process disappears on the eighteenth. The vertebrae immediately posterior to the second either do not have the pit or it Is very much reduced. One, possibly the third, has the spine elevated and rather rugose. The neural arch Is very wide, and extends out directly into the transverse process, which bifurcates Into upper and lower parts for the rib. The next vertebra following has the spine lower, and there is a deep pit, narrow anteroposterlorly but extending across the spine; the bottom and sides of the pit are smooth. The spine extends much farther posteriorly than the centrum; the posterior end is wider and Incloses the anterior end of the following vertebrae. The articular faces of the zyga- pophyses of all the dorsal vertebrae are nearly horizontal. The zygosphene and zygantrum continue through the s
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
