204 
SELACHII. 
P, 1413. Seven imperfect examples ; Armagh. Eger ton Coll. 
46818. Small specimen ; Derbyshire. Gilbertson Coll. 
P. 5355. Ten fragmentary small dental plates ; Ticknall, S. Derby¬ 
shire. The two most nearly perfect specimens are shown 
of the natural size in PI. I. figs. 23, 24. Wilson Coll. 
PoeeilodtJts gibbosns, Davis. 
1883. Poecilodus gibbosus , J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 445, pi. liii. fig. 27. 
Type. Detached dental plate ; British Museum. 
Maximum antero-posterior diameter of the dental plate not much 
greater than its breadth; coronal corrugations numerous, continuous. 
Anterior diverging ridge small, the posterior very prominent, though 
not affecting the extreme postero-lateral margin; inner margin 
deeply sinuous. 
Form. Sf Loc. Lower Carboniferous Limestone : Armagh and 
Sligo, Ireland. 
(i.) Founded variety (? upper jaw). 
P. 2483-4. Type specimen, and two similar dental plates; Armagh. 
Enniskillen Coll. 
P. 2404 a. A smaller dental plate, probably of this species ; Armagh. 
Enniskillen Coll. 
(ii.) Angulated variety (? lower jaw). 
P. 2405. Nearly complete tooth, shown, of the natural size, in 
PI. YI. fig. 23 ; Caljnoney, Sligo. Enniskillen Coll. 
An undetermined species, possibly of Poecilodus , is indicated by the 
following tooth, which exhibits no ridges extending from the outer 
to the inner border :— 
42231. Tooth measuring 0013 by 0-007, the transverse rugae few 
and irregular : Carboniferous Limestone : Oreton, Shrop¬ 
shire. Baugh Coll. 
The following species have also been founded upon detached 
teeth, hut there are no examples in the Collection:— 
Poecilodus carbonarius, St. John & Worthen, Pal. Illinois, vol. vii. 
(1883), p. 139, pi. viii. figs. 20. 21.—Upper Coal Meas¬ 
ures; Illinois and Kansas, XJ.S.A. 
