196 
SELACHII. 
border is broad, rounded, and placed nearest the antero-lateral 
margin. 
The dental plates of one jaw (presumably the lower) are much 
more inrolled than those of the opposing jaw. 
Beltodns sublsevis (M‘Coy). 
1843. Pcecilodus sublcevis, L. Agassiz, Rech. Poiss. Foss. vol. iii. p. 174 
(name only). 
1843. Pcecilodus parallelus, L. Agassiz, tom. cit. p. 174 (name only). 
1855. Pcecilodus sublcevis, F. M/Coy, Brit, Palseoz. Foss. p. 640, 
pi. 3 1 . figs. 7, 8, 9. 
1855. Pcecilodus parallelus, F. M‘Coy, op. cit. p. 640, pi. 3i. fig. 6. 
1862. Deltodus sublcevis, Morris & Roberts, Quart. Journ. Geol. Soc. 
vol. xviii. p. 100 (name only). 
1883. Deltodus sublcevis, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 428, pi. Iii. figs. 7-9. 
1883. Deltodus expansus, J. W. Davis, tom. cit. p. 431, pi. liii. fig. 11. 
1883. Pcecilodus jonesii, J. W. Davis, tom. cit. p. 442, pi. liii. fig. 22. 
Type. Detached dental plates ; Woodwardian Museum, Cam¬ 
bridge. 
A comparatively small species, the maximum transverse measure¬ 
ment of the supposed lower posterior dental plates being about 0-02. 
Transverse ridges and furrows of the dental crown numerous, 
rounded, and very prominent in unabraded specimens. The promi¬ 
nent elevation extending from the outer to the inner margin is 
gently rounded, gradually passes into the narrower postero-lateral 
flattened portion of the plate, and immediately adjoins the antero¬ 
lateral margin ; inner margin gently undulating. 
D. expansus , Davis, appears to be founded upou a crushed abraded 
“ lower” dental plate of this species. 
Form. Sf Loc. Lower Carboniferous Limestone: Armagh, Ireland. 
(i.) Slightly curved variety of posterior dented plate (? upper jaw). 
P. 2442-3. Two plates described and figured by J. W. Davis, loc. 
cit. p. 428, pi. Iii. figs. 7, 8. Ennislcillen Coll. 
P. 2444. Twenty specimens variously abraded. Ennislcillen Coll. 
P. 1450-1. Eight similar specimens. Egerton Coll. 
(ii.) Narrow dented plates placed in advance of the posterior dented 
plates, the more incurved examples referable to the “lower” jaw, 
the others probably to the “ upper.” 
P. 2445 a. Fourteen specimens. 
Enniskillen Coll. 
