328 
SELACIIII. 
or four in number and small; base-line of crown gently arched. 
Supposed lower anterior teeth very minute, with well-separated 
lateral cusps. 
Form, 6f Log. Chalk : Kent. 
36908. Type specimen, described, with a very imperfect figure, by 
Mackie, loc. cit.; Lower Chalk, Dover. Purchased, 1862. 
Nearly complete mandibular and hyoid arches, with a por¬ 
tion of the right (? upper) dentition, and a few teeth on 
the left, described and figured by the present writer, Proc. 
Zool. Soc. 1886, p. 218, pi. xx.; Kent. The pterygo- 
quadrate measures about 0*075 in length, and exhibits a 
facette for a postorbital articulation with the cranium; 
the hyoid arch is notably slender. An anterior tooth, 
probably of the upper jaw, is shown, of three times the 
natural size, in PI. XI. fig. 17 } and a posterior tooth, 
similarly enlarged, in fig. 20. Toulmin Smith Coll. 
47287. Fragments of cartilage associated with shagreen and a few 
teeth; Lower Chalk, Dover. One tooth, representing 
about the fourth lateral series, is shown, of three times 
the natural size, in PI. XI. fig. 18, and another, of about 
the sixth series, similarly enlarged, in PI. XI. fig. 19. 
The shagreen-granules are marked by prominent ridges, 
terminating in a denticulated margin. Gardner Coll. 
41909. Fragments of jaws, with a few teeth, mostly of the upper 
anterior series ; (?) Burham. Mrs. Smith's Coll. 
49032. Imperfect remains of the head, pectoral arch, and the ante¬ 
rior half of the vertebral column, exposed from beneath, 
noticed by the present writer, Proc. Zool. Soc. 1886, 
p. 223. The base of the cranium exhibits a longitudinal 
raised line, evidently the remains of the primitive invest¬ 
ment of the notochord ; each half of the pectoral arch is 
long, slender, and tapering distally; and the vertebrae are 
asterospondylic, a few being shown, of the natural size, in 
IT. XII. fig. 6. Mrs. Smith’s Coll. 
43124. Anterior upper tooth ; Gravesend. Wether ell Coll. 
P. 4100. Minute anterior upper tooth, doubtfully referable to this 
species ; near Margate, Kent. 
Presented by Sydney C. Cockerell, Esq., 1883. 
49960. An imperfect antero-lateral tooth, doubtfully referable to 
S. clubrisiensis ; Glynde, Sussex. Capron Coll. 
