COCHLIODOXTLDJE. 
211 
Dental plate extremely elongated antero-posteriorly ; hinder tumid 
portion passing gradually into the anterior flattened portion; the 
latter portion longer than the former, and crossed by a small, faint, 
very oblique ridge. 
This is supposed to be the upper dental plate of Deltopty chius 
acutus by St. John and ATorthen l . 
Form. § Log. Lower Carboniferous Limestone : Armagh, Ireland. 
P. 2419-20. Type specimens. Enniskillen Coll. 
P. 2421. Thirty similar dental plates, the largest having an antero¬ 
posterior measurement of 0-053. Enniskillen Coll. 
P. 1401. Pour similar specimens. Egerton Coll. 
28729. Two imperfect dental plates. Purchased, 1853. 
A small variety, not distinctly separable from Streblodus colei upon 
present evidence, appears to be indicated by the following speci¬ 
mens :— 
P. 4905. Two dental plates, one figured, of the natural size, in 
PI. A I. fig. 25 ; Yoredale Locks (Upper Carboniferous 
Limestone), AUensleydale, Yorkshire. Horne Coll. 
P. 5349. Pour portions of dental plates, somewhat larger; Upper 
Carboniferous Limestone, Ticknall, near Alelbourne, S. 
Derbyshire. Wilson Coll. 
Streblodus egertoni, Davis. 
1862. Streblodus egertoni, Morris & Roberts, Quart. Journ. Geol. Soc. 
vol. xviii. p. 101 (name only). 
1883. Streblodusegertoni, J. AAA Davis, Trans. Roy. Dublin Soc. [2] vol. i. 
p. 426, pi. liii. figs. 7, 8. 
Type. Detached dental plates ; Eritish Museum. 
A comparatively small species, the antero-posterior measurement 
of the largest known dental plate being 0*014. Hinder tumid por¬ 
tion of plate sharply separated by an abrupt elevation from the 
anterior portion, and about equal to it in extent; anterior portion 
flattened, only crossed by one small angulated ridge, near to and 
parallel with the antero-lateral margin. 
Foi on. Loc. Lower Carboniferous Limestone: Bristol. 
P. 2422-3. Type specimens. Enniskillen Coll. 
20575. Similar dental plate. Purchased , 1845. 
p 2 
1 Pal. llinois, vol. vii. p. 92. 
