104 BRITISH FOSSIL REPTILES. 



vertebra the extent of tbe rib from the head to the tubercle is 2 inches 9 lines. 

 In the tenth vertebra it is 1 inch 7 lines. The rib presents a shallow canal along 

 its posterior surface ; it is nearly an inch in thickness. An extent of upwards of 

 10 inches of the body of the rib {pi, PI. 49) is preserved on the right side of this 

 portion of the thorax of Scelidoiherium. 



The anterior dorsal vertebrae have been partially dislocated, especially the fourth 

 from the fifth, apparently by pressure acting through the scapula (si) upon the diapo- 

 physis and spine of the fifth dorsal. Beyond the scapula the vertebra have retained 

 their natural position and connections, which seems to indicate the action of pressure 

 whilst decomposition of the soft parts was going on in the carcass. Nine of the 

 consecutive vertebra in the fourth block occupy the extent of 1 foot 9 inches. The 

 breadth of the last of these vertebra (PI. 49, D lo), across the diapophyses ( ^), is 



5 inches 4 lines. The total height of the eleventh dorsal vertebra (PI. 52, fig. 1) is 



6 inches. The breadth of the centrum at the fractured part, near the anterior surface, 

 is 1 inch 6 lines. The depth of the centrum, from the floor of the neural canal, is 

 2 inches. The breadth of the neural arch across what are called the " pedicles" is 

 1 inch 8 lines. The height of the neural spine is 2 inches 6 lines. 



As the vertebrae approach the sacrum the bodies gradually increase in depth, 

 without g-aiuinff in breadth, until at the last dorsal the centrum, near its middle 

 part, measures 2| inches in vertical and 1 inch 7 lines in transverse diameter ; a 

 slight longitudinal impression on each side produces the contour of the transverse 

 vertical section figured in PI. 52, fig. 2. The neural canal here gives a triangular 

 section, with the apex downward and sinking into the substance of the centrum, 

 but the sutural limit between centrum and neural arch are indiscernible. The 

 diapophyses decrease in breadth and also in length, and now support the rib by a 

 terminal, slightly notched, articular facet. The ribs, here with simple heads, 

 become shorter and less curved ; a few, as in PI. 51, fig. 1, pi, have suffered fracture, 

 with very little displacement. In different parts of the matrix of the blocks (Pis. 

 49 and 51) are portions of long and slender bones, which are, most probably, 

 abdominal ribs. 



In the sixth block the hinder half of the last dorsal and one lumbar vertebrae 

 are associated with the pelvis ; the lumbar vertebra (PL 53, l) had been dislocated 

 downwards from its articulations with the sacrum. 



The four vertebrse of this part (PI. 63), with the iliac bones (62), are preserved 

 almost in their natural relative positions, the sacral vertebrae having their neural 

 spines and transverse processes exposed. Those of the first sacral (s, 1, rf, ;;/) stand 

 out horizontally and transverse to the axis of the body ; a slight swelling {d), about 

 one inch from their origin, may indicate the point of confluence of the pleurapo- 

 physial {pi) with the par- and diapophysial elements of this part. It is A\ inches 

 in length ; at its base it is 1 inch in thickness and 2 inches in depth, expanding in 



