122 BRITISH FOSSIL REPTILES. 



side, with tlie exception of the few remains above noticed, were in the matrix so 

 detached. The characters of the caudal vertebrsB figured in Pis. 55 and 56 were 

 displayed by careful removal of the matrix left adhering to the parts originally 

 exposed ; during which operation the portions of the dermo-lateral bones which had 

 been pressed inward, and contributed to the dislocation of the twenty-first from the 

 twenty-second, and of the eighteenth from the nineteenth caudal vertebras, were 

 brought to lig'ht. 



A dermo-neural bone overlies the ninth and tenth caudals (PI. 55, fig. 1) ; 

 another over the seventh and eighth [d n) ; a third over the sixth and fifth. The 

 fracture through the middle of this latter bone (PL 54, fig. 3), shows the form and 

 depth of the angular excavation at its base, which rested, probably with interposed 

 ligamentous substance, upon the summit of the neural spine of the caudal. The 

 corresponding dermo-heemal bones, displaced so as obliquely to overlap the h^mal 

 spines on the right side, are also preserved ; and on this side there are as many 

 dermo-lateral scutes, but more fragmentary and dislocated. 



In the block of lias with the first caudal vertebrse (PI. 54, figs. 1 and 2), is the 

 anterior half of the dermo-neural overlapping the fifth and sixth of that series. 

 Two similar bones with a basal excavation exposed by fracture in one of them, are 

 situated to the right side of the fourth and third caudals, which may be dermo- 

 laterals or displaced dermo-neurals. A portion of a massive dermal bone lies upon 

 a part of the ilium contained in this slab. The rest of the armour of this part of 

 the base of the tail has been removed. The like is the case with regard to the 

 upper part of the block including the sacrum (PL 55). At its under part, in which 

 are imbedded dislocated bones of the hind limbs, there are a few scattered portions 

 of wedge-shaped dermal bones, similar in size to those at the base of the tail, but 

 less pyramidal, and with more obtuse summits. A few smaller, flatter, subcircular 

 dermal bones were met with in the course of exposing the parts of the endo-skeleton. 

 One of these (ib., d), lies above the interspace between the left ilium and the third 

 sacral rib (PL 55, fig. 1, d). 



In the block of lias containing the fore part of the thorax and scapular arch a 

 longitudinal series of eight dermal bones were found on the right side, overlapping 

 the ribs, external to the diapophyses. These dermal bones were shorter and thicker 

 than the caudal dermo-neurals, and had been subject to more or less fracture and 

 some displacement. The best preserved was wedge-shaped, with the sides of the 

 excavated base slightly convex, 2 inches in length, 8 inches 9 lines in breadth, the 

 sides converging at a more open angle, but unequally, to a margin which shows a 

 convex ridge. The inferior size and unsymmetrical shape of this bone seem to 

 show that it formed part of a lateral row, which had been situated near a middle 

 one, or had ranged along near the medial line of the back. The margins of these 

 bones wei-e not entire. The summit of a dermo-neural spine remains wedged 



