. Carnegie Institution of Washington publication. Fig. 20.—Diasparactiis zenos Case. Lateral view of the ninth to tlie twenty-third cau- 3- From this point back the character of the vertebrae changes regularly and very slightly. The last trace of a rib is seen on the eleventh or twelfth. The sixteenth and seventeenth still have well-formed netiral arches located on the anterior half of the centrum; the posterior zygapophyses are elongated. From this point back to the twenty-third, the last preserved, the neural spines are low, almost rudi- mentary, and the zygapophyses are elongated, interlock
. Carnegie Institution of Washington publication. Fig. 20.—Diasparactiis zenos Case. Lateral view of the ninth to tlie twenty-third cau- 3- From this point back the character of the vertebrae changes regularly and very slightly. The last trace of a rib is seen on the eleventh or twelfth. The sixteenth and seventeenth still have well-formed netiral arches located on the anterior half of the centrum; the posterior zygapophyses are elongated. From this point back to the twenty-third, the last preserved, the neural spines are low, almost rudi- mentary, and the zygapophyses are elongated, interlocking strongly at first, but becoming reduced in the posterior part of the tail. In only the last few vertebra is there any tendency for the centra of the vertebrae to become at all elongate, and even here it is very slight. There is no indication of any great length of tail. The ribs: Anterior to the first vertebra in series, reckoned as the third cervi- cal, there is a well-developed rib, of moderate length, lying in the matrix just within the edge of the scapula. This is the rib of the axis; it has a wide, undivided head and a slender shaft terminating in a point. The ribs of the third, fourth, and fifth vertebrae are in general form similar to the ribs of the same vertebrae in D. phaseolinus, but as they are injured on the left side and covered by the scapula on the right, the exact form can not be given. The rib of the third vertebra (fig. 21 a) has an elongate, undivided proximal end; beyond this it contracts to a narrow shaft; the anterior edge is straight to the distal end, but the posterior is extended backward in a sharp point almost at right angles to shaft for a centi- meter or more and then obliquely forward to the distal end; this gives a narrow, triangular form to the rib, resembling the same rib in D. phaseolinus, but longer. The shape of the next two ribs is less certain, but they are larger than the third and were evidently of the same triangtilar form. The fi
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1913
