620 PROF. H. G. SEELEY ON THE DINOSAURIA OF 
spongy tissue of the most delicate character. Throughout the 
whole of these specimens the external surface is remarkably dense, 
and seems to have resisted decomposition to an unusual degree ; 
while the cartilaginous surfaces have more frequently suffered 
Fig. 5.—Siateenth Caudal Vertebra of Eucercosaurus tanyspondylus, 
two thirds nat. sizé. 
‘ 
yi ay 
a. Left lateral view. 6. Superior view. c. Anterior view. 
decay. ‘The isolated neural arch is much invested with phosphate 
of ime, but does not differ essentially from the neural arch at- 
tached to an early caudal vertebra, except that the transverse pro- 
cesses and platform are above the level of the neural canal. This 
proves the arch to be either cervical or dorsal. The indications of 
the facets of the zygapophyses show that the centrum was probably 
1,5 inch long, so that the arch would correspond in size with the third 
dorsal vertebra described. The posterior zygapophyses measure 
1 inch transversely, and are notched out to a moderate extent pos- 
teriorly ; the facets are small and look obliquely downward and 
outward. ‘The anterior facets are broken away, but appear to have 
been limited laterally by remarkable tubercles. The transverse 
processes were compressed concayely, notched out in front of the 
posterior zygapophyses, and extending outward from the vertical 
laminee of the neural arch, which are imperfectly preserved. The 
transverse processes, like the neural spine, are fractured. 
