HYBODUS — CLADODUS — PLEUROPLAX — HELODUS SIMPLEX. 
201 
Mr. Quilter appears also to have found “ an imperfect hooked cephalic spine 
(Sphenonchus) of a Hybodont Shark,” which may belong to this, or to an 
allied species. (See ‘Trans. Leicester Lit. and Phil. Soc.,’ April, 1889, p. 20.) 
Hybodus, Agassiz (sp. inc.). 
The Museum possesses a tooth from the Lower Lias {Bucklandi zone), 
Crown Hill, Evington. 
The Museum of Practical Greology, Jermyn St., London, possesses a spine 
from the Rhmtics of Wigston. 
A tooth, apparently referrible to this genus, was found by Mr. E. Wilson, F.Gr.S., 
from the Middle Lias Marlstone, Belvoir, and recorded at p. 158 ‘Mid. Nat.,’ 
vol. viii. 
In Rutland. — According to Mr. R. Etheridge, F.R.S., remains have been 
found in the Gireat Oolite, Belmesthorpe (see Appendix ‘ Memoirs of the Gieological 
Survey,’ 1875, p. 291). 
Cladodus ==(?) Sphenacanthus, Agassiz. 
Teeth are reported from the Coal Measures, Ashby-de-la-Zouch Coal-Field 
(see Appendix ‘ Burton-on-Trent : its History, its Waters, and its Breweries,’ 
by W. Molyneux, F.Gr.S., 1869); Mr. A. S. Woodward kindly informs me: — 
“ The Coal-Measure ‘ Cladodus ’ is not Hybodus, and I think it is very doubtful 
if it be the same as the true Cladodus, Agassiz. In the British Museum 
Catalogue, just published, I have assigned the Coal-Measure teeth to 
Sphenacanthus, Agassiz.” 
Family C 0 C H L 1 0 D 0 N T ID ^ (? CESTEACIONTID.^ ). 
Pleuroplax attheyi (Barkas). 
Reported from the Ashby Coal-Field by W. Molyneux (Appendix op. cit.), 
under its former manuscript name of Poecilodus angustus. 
Pleuroplax rankinei (Hancock and Atthey). 
Reported from the Ashby Coal-Field (Appendix op. cit.) under its former 
generic name of Pleurodus. 
Pleuroplax, A. S. Woodward (sp. ind.). 
Reported, under the name of Pleurodus, from the same place as the pre- 
ceding, and probably referrible to one of the above species. 
Helodus simplex, Agassiz. 
Recorded from the same place as the preceding. 
