324 MR. T. ATTHEY ON ANTHEICOSAURUS EUSSELLI. 



short space, and ends below the posterior margin of the dentary 

 bone. 



The teeth are arranged in a donble series (maxillary and pala- 

 tal) on each side of the upper jaw, and in a single series on each 

 side of the lower jaw. They are of pretty uniform size and 

 shape throughout, excepting the palatal tusks. Those of the 

 mandible are anchylosed externally to the alveolar margin ; and 

 a thin lamina of bone, running continuously over their inner 

 sides, invests them as in Loxomma. They are, at their bases, 

 oval in outline, the long diameter of the oval being placed trans- 

 versely to the line of the jaw. Above the alveolar margin they 

 are circular up to near their apices, where a ridge exists on each 

 side, giving the teeth a double edge. They are longitudinally 

 grooved, with flattened ridges between from the alveoli up to 

 near their apices. The whole surface of the teeth is coated with 

 a layer of enamel, which is thickest at the apex. 



VertehrcB. — Thirty- six vertebras were found in connexion with 

 the skull : — first, a small one, which has been pressed in upon 

 the skull between the supratemporal and the pterygoid bones, 

 and belongs probably to the upper part of the neck. The re- 

 maining thirty -five are embedded in two separate slabs of shale : 

 the smaller slab shows six vertebras, all in a connected series ; 

 one of these is figured in Plate VIII., fig. 4. The larger slab has 

 twenty-nine vertebrae, also in a connected but contorted series, 

 and lying nearly in their natural order, with their dislocated 

 and broken processes around and several ribs lying beside them. 



The vertebras are alternately large and small, well ossified and 

 preserved; and the anterior and posterior surfaces of their bodies 

 are both somewhat concave. 



The bodies are broadly rounded and project downwards; and 

 the space between the anterior and posterior surfaces is concave 

 from side to side, grooved, and pitted in the grooves ; the under 

 margin of the body is thicker than the margin bounding the 

 vertebral canal; so that the spinal column at that part must 

 have been convex on its abdominal aspect ; moreover the bodies 

 are peculiar in having the upper borders of their anterior sur- 

 faces projecting forwards in the form of a ridge, whilst the lower 



