236 
SELACHII. 
Form. 4" Loc. Lower Carboniferous (Burlington Limestone) : 
Iowa, U.S.A. Keokuk Limestone : Indiana {Newberry). (?) Cleve- 
land Shale : Ohio. 
P. 2727. Tooth with much pointed eminences ; Augusta, Iowa. 
Ennislcillen Coll. 
Orodus tenuiS) Davis. 
1883. Orodus tenuis, J. W. Davis, Trans. Roy. Dublin Soc. [2] vol. i. 
p. 399, pi. li. fig. 14. 
Type. Detached abraded tooth ; British Museum. 
Founded upon a much abraded imperfect tooth, long and nar- 
row, with very high pointed median eminence, and with an angu- 
lated longitudinal median crest. Only two transverse wrinkles 
remain at the base of tho median cone. 
Form. Loc. Lower Carboniferous Limestone : Armagh, Ireland. 
P. 2710. Typo specimen. Enniskillen Coll. 
Orodus (?) gibbus, Davis. 
1843. Orodus yibhus, .1. K. Portlock (e.v Agassiz, MS.), Rep. Geol. 
Londonderry, p. 401 (name only). 
1883. Orodus yihlms, J. W. Davis, Trans. Roy. Dublin Soc. [2] vol. i. 
p. .390, pi. li. figs. 6, 7. 
Type. Detached tooth ; British Museum. 
A very doubtful species founded upon tho teeth mentioned below. 
The median eminence is prominent and gibbous ; there is no longi- 
tudinal crest, and the transverse wrinkles are reduced to small 
marginal crcnulations. 
Form. ^ Loc. Lower Carboniferous Limestone : Armagh, Ireland. 
P. 2704-5. Type specimens, the second very suggestive of a tooth 
of Psephodus maynus. Enniskillen Coll. 
P. 2709. Three teeth regarded as probably belonging to this species 
by J. W. Davis, loc. cit. Enniskillen Coll. 
Tho following species have also been founded upon detached 
teeth, but there are no examples in the Collection : — 
Orodus alleni, St. John & Worthen, Pal. Illinois, vol. vi. (18/5), 
p. 310, pi. vii. fig. 19. — Low’er Coal-Measures ; Iowa. 
Orodus earinatus, St. John & Worthen, op. cit. vol. vi. p. 30/, 
pi. V. fig. 24. — Keokuk Limestone ; Iowa. 
Orodus collctti, J. S. Newberry, Ann. Rep. Geol. Surv. Indiana, 
1876-78 (1879), p. 343.— St. Louis Limestone ; Indiana. 
Orodus compressus, F. M‘Coy, Ann. Mag. Nat. Hist. [2] vol. n. 
