242 
SELACHII. 
suggestion marie, with liesitation, by Dr. Traquair, and adopt the 
provisional name of Sphenaeanthus for the fish. 
Sphenacanthus serrulatus, Agassiz. 
1837. SpJienacemthns serrulatm, L. Agassiz, I’oiss. Foss. vol. iii. p. 24, 
pi. i. figs. 11-1.3. 
1884. Ctenacanlhus (P) serndatus, R. II. Traquair, Geol. 5Iag. [3] vol. i. 
p. G. 
Type. Imperfect dorsal fin-spine ; Edinburgh 'Museum. 
The type species known only by the dorsal fin-spine, which attains 
a ma.ximura length of about 0-15, and is ornamented by sharp 
ridges, in part sparsely nodose. 
Form. ^ Loc. Calciferous Sandstones : Burdiehouse, near Edin- 
burgh. 
15506 a. Very imperfect .spine ; Burdichouse. Piti-chased. 
Sphenacanthus costellatus (Traquair). 
1884. Ctenacanthm costellatus, R. II. Traquair, Geol. Mag. [3] vol. i. 
p. 3, pi. ii. 
(?) 1888. Ctenacanthm costellatus (?), R. H. Traquair, loc. cit. vol. v. 
p. 81. 
Type. Nearly complete fish ; British Museum. 
Crown of tooth with slender cusps almost or quite smooth. Ribs 
of the dorsal fin-spines ornamented with numerous finely-grooved 
tubercles. 
Form. Loc. Calciferous Sandstones : Dumfriesshire. 
P. 5900. Type specimen, partly preserved in counterpart, described 
by 11. II. Traquair, he. cit., 1884. Purchased, 1883. 
Sphenacanthus hybodoides (Egerton). 
1853. Ctenacanthus hybodoides. Sir P. Egerton, Quart. Journ. Geol. 
Soc. vol. ix. p. 280, pi. xii. 
186.3. Ctenacanthus nodosus. Sir P. Egerton, ibid. p. 281. 
1809. Ctenacanthus major, .1. Thomson, Brit. Assoc. Rep., Trans. Sect. 
p. 102. 
1871. Ctenacanthtts hybodoides, J. Thomson, Trans. Geol. Soc. Glasgow, 
vol. iv. pt. i. p. 69, pis. ii., iii. 
1873. Ctenacanthus (? and Cludodus), T. P. Barkas, Coal-Meas. Palmont. 
p. 21, figs. 4.3-68 (Pp. 19, figs. 31-.34). 
1874. Ilybodus, W. J. Barka.s, Geol. Jlag. [2] vol. i. p. 103. 
