PETALODONTIDiE. 
53 
Form. Sf Loc. Lower Carboniferous Limestone : Armagh, Ireland. 
Carboniferous Limestone : Shropshire (Davis), Derbyshire (McCoy). 
P. 3000-2. Specimens figured by J. W. Davis, Trans. Eoy. Dublin 
Soc. loc. cit.; Armagh. Enniskillen Coll. 
P. 3003. Twenty teeth ; Armagh. Enniskillen Coll. 
P. 3004. Twelve teeth; Tynan, Armagh. Enniskillen Coll. 
P. 1443. Six teeth; Armagh. Egerton Coll. 
28538, 28735, 28921, 28927, 38504. Twenty-two broken teeth; 
A r m o oh ^Purchased. 
The following species have also been founded upon detached teeth, 
but there are no examples in the Collection:— 
Ctenoptychius acuminatus : Pristodus ? acuminatus , St. John & 
AVorthen, Pal. Illinois, vol. vi. (1875), p. 402, pi. x.a. fig. 6. 
—Kinderhook Limestone ; Iowa. 
Ctenoptychius bellulus: Ctenopetalus bellulus , St. John & AVorthen, 
tom. cit. p. 398, pi. xii. fig. 9.—St. Louis Limestone ; Iowa, 
Illinois. 
Ctenoptychius compactus : Harpacodus compactus, St. John & "Wor¬ 
t-hen, tom. cit. p. 355, pi. x.a. fig. 1.—Chester Limestone; 
Illinois. 
Ctenoptychius elegans : Serratoclus elegans , L. G. de Eoninck, Faune 
Calc. Carbf. Belg. pt. i. (1878), p. 54, pi. vi. fig. 12.—U. 
Carboniferous Limestone ; Vise, Belgium. 
Ctenoptychius limatulus'. Ctenopetalus limatulus, St. John & AVor- 
then, tom. cit. p. 399, pi. xii. fig. 18.—Chester Limestone; 
Illinois. 
Ctenoptychius mediusi Ctenopetalus medius, St. John & Avorthen, 
tom. cit. p. 400, pi. x.a. fig. 26.—Chester Limestone; Illi¬ 
nois. 
Ctenopty chius occidentalis 1 : Ctenopetalus occidentalis , St. J ohn & 
AVorthen, tom. cit. p. 401, pi. xii. fig. 14.—Lower Coal- 
Measures; Iowa. - Md . 
Ctenoptychius pertenuis , St. John & AVorthen, tom. cit. p. 382, 
pi. x. a. fig. 27.—Chester Limestone ; Illinois. 
Ctenoptychius semicircular is, Newberry & A\ orthen, Pal. Illinois, 
1 If, as the present writer considers, the tooth described oy St. John & or- 
then (t° m - ctt- P- 355, pi. x.a. fig. 2) as Harpacodus occidentalis must be placed 
in Ctenoptychius , and if these two species are distinct from all others, one will 
require a new specific name. 
