83 
Vertebrae . None of the cervical vertebrae are preserved. 
There are sixteen dorsal vertebrae present, though the anterior one 
is in a poor state of preservation and the first two and the last three lack 
the neural spines (Plate XVII, figure 1). These are thought to represent 
numbers one to seven aud ten to eighteen, respectively. A comparison 
of these vertebra? with the type of T. edmonloni points to the probability 
of there being twenty dorsals in the complete series of T. saskalchewanensis, 
as in T. edmontoni, rather than eighteen as given by Marsh for T. annedens. 
The anterior dorsals are strongly opisthocoelous, but proceeding 
backward the posterior face becomes less concave and the anterior face 
less convex, until in the last three the anterior faces are nearly fiat. The 
sides are concave antero-posteriorly and ventrally a longitudinal ridge 
connects the two ends. Proceeding backwards the centra increase in 
height and breadth, but there is very little change in the length from the 
second to the end of the series, as preserved, except that the posterior 
ones are inclined to shorten. 
The neural spines are incomplete in some cases, but appear t-o increase 
in length from the front backwards. Their fore and aft breadth increases 
to the eleventh, from which point they gradually decrease as far back 
as they are preserved. They stand nearly erect. In the neural spines, 
of the median dorsals, the posterior edge is convex, thus making the fore 
and aft breadth greatest below the top of the spine. This posterior 
convexity reaches its maximum development in the eleventh dorsal. In 
these spines the anterior face is slightly concave. Measuring from the 
top of the lateral process the neural spine of the third dorsal is 115 mm. 
high and 60 mm. in fore and aft breadth, the eleventh is 133 mm. high 
and 88 mm. in greatest breadth, and the fifteenth is 155 mm. high and 
55 mm. broad at midheight. 
The transverse processes are long and heavy and are inclined strongly 
upward in the anterior vertebrae, but stand more nearly at right angles 
to the erect neural spine in the posterior ones. They are inclined back- 
ward to a greater degree than the neural spines, especially in the anterior 
vertebrae. The parapophysis is at the base of the neural arch in advance 
of the midlength, in the anterior dorsals, but proceeding backwards it 
works up the side of the transverse process until in the fifteenth it is midway 
between the base of the arch and the end of the transverse process. 
The caudal series is represented by thirty-seven vertebrae, all but one 
of which lack the neural spines. Most of them were washed out of the 
bank, so it is impossible to positively place them in the series, but it is 
thought that not more than two of the anterior ones are missing. The 
first two of the series do not show facets for the attachment of chevrons 
and the third has poorly developed facets; from the fourth back the 
facets are well developed. Twenty-five of these are thought to represent 
the anterior portion of the tail; the other twelve constitute a continuous 
series from near the extremity. 
In the anterior caudals the anterior face is slightly convex and the 
posterior face is concave, whereas in the posterior ones both faces are 
flat {See Plate XVII, figures 2 and 3), The centrum of the most anterior 
caudal is nearly twice as broad as long and the anterior and posterior 
faces are circular in cross-section, with a very slight flattening above and 
