MORPHOLOGY OF BAROSAURUS LENTUS. 23 
Measurements of Caudal II Barosaums 
lenttis 
mm. 
Centrum, length : 172 
anterior face, height 280 
" width 385 
" circumference 1010 
posterior face, height 245 
" width 315 
Pleuroccele, length 72 
depth 173 
Neural canal, height 36 
" width 44 
Width across pedicels (maximum) 128 
Height to prezygapophyses 435 
Height to postzygapophyses 410 
Caudal III (Vertebra K) (PI. V, Figs. 1-3). — This bone is very finely preserved 
even to the diapophyses, the more perfect right one being supplemented completely by 
the left. 
The anterior face of the proccelous centrum is deeply concave, the ratio of depth 
to width of the curve being about 1 : 4. This may be very slightly exaggerated by 
crushing. The neural arch is strong. Heavy buttresses, prezygapophysial lamina?, sup- 
port the zygapophyses, reinforced by lighter oblique ones, which originate above the 
neural canal, where they arise as the keystone of the arch which overhangs the aperture 
of the canal. The prezygapophyses are well developed and face inward and upward at 
an angle of about 45 degrees. Above them rises the neural spine, somewhat asym- 
metrical as in the posterior dorsals, especially as to the position of the rugose prespinal 
lamina. The diapophyses have a ventral, more or less horizontal portion, upon which 
there arises at right angles a thin, expanded, vertical plate ; this in turn is bounded on 
its outer margin by the rugose diapophysial lamina, which is expanded antero-posteri- 
orly. A strong oblique buttress arising from the pedicel runs across the anterior face 
of the otherwise thin diapophysial plate, and abuts against the inner side of the lamina 
in its upper portion. Width across zygapophyses, 180 mm. Vertical extent of right 
diapophysial lamina, 280 mm. 
Lateral aspect (right) (PI. V, Fig. 2). — The centrum has a very deep pleuroccele, 
partially occluded by matrix. The pleuroccele lies in the upper half of the centrum. 
The large diapophysis overhangs the side of the centrum, and in front of the diapophy- 
sial plate there is another pleuroccele-like depression impressed into the pedicel as well 
as the upper portion of the centrum. This is also occluded by matrix, so that its depth 
may not be learned, but its height is 90 mm. and the antero-posterior diameter 67 mm. 
The neural spine is inclined slightly backward, so that it overlies the rear half of the 
centrum. The spine is reinforced by thin lamina? of bone. The diapophysial lamina 
rises vertically from the diapophysis, and another, almost horizontal one originates 
about the same place and runs to the postzygapophyses. There is a heavy rugosity on 
the upper half on the lateral aspect of the spine, which is deeply channeled to reduce 
weight. 
The posterior aspect is not so well preserved, as distortion is in greater evidence 
than in front. The width across the pedicels is 125 mm. ; of the neural canal, 45 mm. ; 
its height, 45 mm. (Compare table below.) 
