Cope.j 246 [Dec. 21, 
The articular extremity is marked with irregular pits as in Dystropheus and 
Cetiosaurus. 
Measurements. M. 
as andvattacie aloU 
Diameter of anterior caudal vertebra: J vertical.......  — .200 
transverse...... .260 
Elevation to zygapophyses of the same.............. .200 
Totalelevation) Of Ghe Same. 260 kee. Be oes oceisinsis scselele ne eOOU 
Leneth:of femiiitin.s, matecsciiey oe eee Cee ee aA ee eo 
Proximal diameter of femur f foreandaft........-.++ 165 
ELAM SVERSE Baye telekecsie ole reiete 410 
Distal diameter of femur § reandaft.............06. .360 
fYARSVETSC: «1.0 agar racic stolen Rae 
Diameter of middle of shaft of femur................ .280 
The caudal vertebree of this species are much more deeply biconcave 
than those of the Camarasaurus supremus ; they also differ in their rela- 
tively and absolutely greater breadth of centrum. 
TICHOSTEUS Cope. 
Paleontological Bulletin No. 26, p. 194 (Published November 21st, 1877). 
TICHOSTEUS LUCASANUS Cope. 
Loe. cit. 
SYMPHYROPHUS Cope. 
Vertebral centra moderately elongate, slightly amphiccelous, and com- 
posed of uniformly and moderately dense osseous tissue. A narrow deep 
fossa in the floor of the neural canal. Neural arch codsified to centrum, 
with a lateral shallow fossa at its base. Neither costal articulation nor pro- 
cess on the centrum. 
The coosification of the neural arch of this genus distinguishes it from 
the few amphiccelous crocodilian genera known from North America, and 
the fossa at its base is so shallow as to separate it from sauria of the 
Preumatarthrus andrOrnithopsis type. 
SYMPHYROPHUS MUSCULOSUS Cope. 
A vertebra of this species is strongly concave laterally and distinctly so 
inferiorly. The anterior articular facets plane, the posterior slightly con- 
cave. The superficial layer of bone is dense and smooth, excepting near 
the edges of the articular surfaces, where it is rugose. The rugosity is 
arranged in a line within the articular faces, and consists of numerous 
small irregular pits and grooves which inosculate. Near the border the 
grooves assume a transverse direction. There is a nutritive foramen near 
the middle of each side of the centrum. There are traces of the neura- 
pophysial suture, showing that the neural arch is distinct in young animals. 
Measurements M. 
antero-posterior...........+.-.- -032 
Diameteriof centrum: < vertically; sm. nese crc cone isin sOem 
tPANS VETGEL eels 1c cidaciosieas eae Ol 
