COCHLIODONTID^. 
215 
(ii.) Inrolled variety (? lower jaw), shown by Agassiz, tom. cit. pi. xiv. 
figs. 32, H3, and by Davis, toin. cit. pi. liii. fig. 18. 
P. 2438. Type specimen ; Bristol. Ennislcillen Coll. 
P. 2440 a. Imperfect dental plate ; Bristol. Ennislcillen Coll. 
20575 a. Imperfect dental plate ; Bristol. Purchased, ISAo. 
P. 1478 B. Two specimens ; Black Hock, Bristol. Eyerton Coll. 
40329. Perfect, though abraded, specimen ; Clevedon, Somersetshire. 
Purchased, 1807. 
P. 1478c. Similar specimen; Hook Point, Wexford. Eyerton Coll. 
P. 5351. Imperfect specimen shown of the natural size in PI. I. 
fig. 21 ; Ticknall, near Melbourne, South Derbyshire. 
Wilson Coll. 
P. 5350. Two fragments of worn dental plates, probably of this 
species ; Ticknall. Wilson Coll. 
The following species have also been founded upon detached 
dental plates, but there are no examples in the Collection : — 
DiltoptycMus e.vpansus, St. John & Worthen, Pal. Illinois, vol. vii. 
(1883), p. 98, pi. V. figs. 9-11 (also figs. 12, 13, Slreblo- 
tfus-platcs).— St. Louis Limestone; Illinois, Iowa, Missouri. 
Delloptyehius nitidus, St. John & Worthen, tom. cit. p. 99, pi. v. 
fig. 16 : Cochliodiis nitidus, J. Leidy, Trans. Amer. Phil. 
Soc. [2] vol. xi. (1857), p. 87, pi. v. fig. 2. — Chester 
Limestone; Illinois. 
I)dto2)tychi.us primus, St. John & Worthen, tom. cit. p. 93, pi. v. 
fig. 6 (also figs. 7, 8, /Sfr€6fof?««-plates). — Upper Burling- 
ton Limestone ; Iowa. 
Deltoptycliius wnchsmuthi, St. John & Worthen, tom. cit. p. 93. 
pi. V. figs. 1, 2 (also figs. 3-5, StreiZorfas-plates). — Keokuk 
Limestone; Illinois, Iowa, and Missouri. 
Deltoptycliius varsouviensis, St. John & Worthen, tom. cit. p. 96, 
pi. V. fig. 14 (also fig. 15, *8</’e?<7ofb»s-plate). — Warsaw 
Limestone ; Illinois. 
As already remarked (p. 205), dental plates of the form hero re- 
garded as Deltoptychius are described by St. John and Worthen as 
Poecilodus vortheni and P. sprinyeri. The Belgian tooth named 
