384 WELLBURN : FISH FAUNA OF LOWER CARBONIFEROUS ROCKS. 
//. levis Davis, I.e., p. 409. 
Syn.: Lophodus levis Davis, I.e., p. 409. 
H. hifurcatus Davis, I.e., p. 408. 
Syn.: Lophodus hifurcatus Davis, I.e., p. 408. 
H. gihberulus (Agassiz) Davis, I.e., p. 405. 
Syn.: Lophodus gihberulus Davis, I.e., p. 405. 
Note. — All the above " Helodont " teeth are in all likelihood 
detached anterior teeth of " Cochliodonts," and many 
probably belong to one and the same fish. 
Dr. R. H. Traquair, F.R.S., has figured and described a 
specimen of Psephodus magnus Agassiz, which shows the teeth 
and cartilages of the jaws. Amongst the teeth shown are some 
typical of Helodus {Lophodus) Icevissimus, H. rudis M'Coy, 
H. planus, and //. [Lophodus] didymus. 
All the above Helodont teeth are in the York Museum 
and Author's col. 
Genus Venustodus St. John and Worthen, Pal. lUinois, 
vol. vi., p. 344, 1875. 
F. serratulus (Davis), A. S. Woodward, I.e., p. 225. 
Syn.: Lophodus serratulus Davis, I.e., p. 408. 
Teeth : York Mus. 
Form and Loc: Carbonif. limestones, Wensleydale. 
Genus Pleuroplax A. S. Woodward, I.e., p. 173. 
P. woodi Davis, I.e., p. 458. 
Dental Plates : York and Brit. Mus. 
Form and Loc: Carbonif. limestones, Wensleydale. 
Genus Psephodus Agassiz (Morris and Roberts), I.e., p. 101. 
P. magnus (M'Coy), Brit. Pal. Foss., p. 622. 
Dental Plate : York Mus. 
Form and Loc: Carbonif. Hmestones, Wensleydale. 
Genus Sandalodus Newberry and Worthen, Pal. Illinois, 
vol. ii., 1866, p. 102. 
S. minor Davis, Quart. Jour. Geol. Soc, vol. xL, p. 626. 
Lower Dental Plates : York and Brit. Mus. 
Form and Loc: Carbonif. limestones, Wensle3^dale. 
