196 
selachii. 
border is broad, rounded, and placed nearest the aiitoro-latoral 
margin. 
The dental plates of one jaw (presumablj’ the lower) aro much 
more inrollod than those of the opposing jaw. 
Deltodus sublsevis (M‘Coy). 
1843. Paxilodus mblavis, L. Agassiz, llech. Poiss. Foss. vol. iii. p. 174 
(name only). 
1843. rcecilodua piirallelm, L. Agassiz, tom. cit. p. 174 (name only). 
1856. Poocilodus sublesvis, F. M'Coy, Brit. Palasoz. Foss. p. 040, 
pi. 3 1 , figs. 7, 8, 9. 
1856. FaxUodus paralklus, F. M‘Coy, op, cit. p. 040, pi. 3i. fig. 0. 
1802. Ddtodm mblmm, Moms & lloberts, Quart. Journ. Geol. Soc. 
vol. xviii. p. 100 (name only). 
1883. Deltodus suhkevis, J. W. Davis, Trans. Hoy. Dublin Soc. [2] 
vol. i. p. 428, pi. lii. figs. 7-9. 
1883. Deltodus expansus, J. W. Davis, tom. cit. p. 431, pi. liii. fig. 11. 
1883. Pmcilodus juHcsii, J. W. Davis, torn. cit. p. 442, pi. liii. fig. 22. 
Type. Detached dental plates ; Woodwardian Museum, Cam- 
bridge. 
A comparatively small species, tlie maximum trausvorse 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 postcro-latcral 
flattened portion of the plate, and immediately adjoins the antero- 
lateral margin ; inner margin gently undulating. 
D. e.vpaimis, Davus, appears to bo founded upon a orushed abraded 
“ lower ” dental plate of this species. 
Form. ^ Loc. Lower Carboniferous Limestone : Armagh, Ireland. 
(i.) Slightly curved variety of posterior dental plate (? up>per jaw). 
P. 2442-3. T wo plates described and figured by J. W. Davis, loc. 
cit. p. 428, pi. lii. figs. 7, 8. Ennislcillen Coll. 
P. 2444. Twenty specimens variously abraded. Ennislcillen Coil- 
'S. 1450-1. Eight similar specimens. Egerton Coll. 
(ii.) Narrow dental plates placed in advance of the posterior dental 
plates, the more incurved examples referable to the “lower” juw, 
the others prohahly to the “ upper.” 
P. 2445 a. Fourteen specimens. 
Ennislcillen Coll. 
