Cope. ] 482 [Sept. 19, 
sandstone in which the bones occur, and one below it. The portions of 
the skeleton found, rested in the midst of vegetable debris, as sticks and 
stems, and was covered with many beautiful dicotyledonous leaves, which 
filled the interstices between the bones. The plant-bed gradually passed 
into a shell-bed, containing numerous thin dimyaria, and close by, some 
oysters were found. The whole question as to geologic age and aqueous 
conditions during which these beds were deposited, being unsettled, I 
gave especial attention to the recovery of the bones, with the view of 
reaching a definite conclusion on these points. 
We succeeded in recovering sixteen vertebre, including a perfect 
sacrum, with dorsals and eaudals; both iliac and other pelvic bones, 
those of one side nearly perfect ; some bones of the limbs, ribs and other 
parts not determined. 
The vertebrae are large. The dorsals are short, with vertically oval 
centra, and small neural canal. The diapophyses originate well above 
the neural canal, diverge upwards, and are triangular in section. The 
neural spine is very much elevated, and the arch short antero-pos- 
teriorly. The zygapophyses are close together in both directions, those 
of the same aspect being separated by a narrow keel only. They no not 
project, but consist of articular surfaces eut into the solid spine. The 
latter is flat and dilated distally. The articular faces are nearly plane 
with a slight median prominence. 
The ribs have two articular surfaces, but I found no capitular pit on 
the dorsal centra. 
Elevation of centrum, 7.5 in. ; width of the same, 5 in. 7.5 lines ; length 
of do. 3 in, 8.5 lines. Total elevation of a dorsal vertebra, twenty-eight 
inches three lines. The sacrum consists of five vertebra, the anterior 
centrum not depressed. They give out huge diapophyses which are 
united by suture. They are themselves united distally in pairs, each 
pair supporting a longitudinal convex articular face for the ilium. Each 
pair encloses a perforation with the centra. The first diapophysis goes 
off from the point of junction of the first and second vertebra, the second 
from the third only, and is more slender. The total length is 25 in. ; 
and the width 30 in. Its vertebrae are flat below, with latero-inferior 
angles. The last centrum gives off a simple diapophysis. 
Another vertebra exhibits a diapophysis as low as the floor of the neural 
canal and united by coarse suture. Others posterior to the sacrum are 
more elongate with slightly compressed centrum, and with diapophysis 
opposite floor of canal and not united by suture. Centra flat below ; no 
chevron bones discoverable. Length centrum, 4 in. 4 lines; depth of 
articular face, 4 in. ; width of do. 4 in. 8 lines. 
The iliac bone is extended antero-posteriorly. One extremity is thick 
and rather obtuse, but of little depth. There is a large protuberance 
above the acetabular sinus. The other extremity is dilated into a flat 
thin plate of rather greater length than the stouter extremity. From 
