PETAL0D0XTID2E. 
43 
1886. Petalodus acuminatus, J. W. Davis, Trans. Roy. Dublin Soc. [2] 
vol. i. p. 494, pi. lix. figs. 22-24. 
1883. Petalodus mequilateralis, J. W. Davis, tom. cit. p. 497, pi. lx. 
figs. 3, 4. 
1884. Petalodus acuminatus, J. W. Davis, Quart. Journ. Geol. boc. 
vol. xl. p. 624, pi. xxvi. fig. 10. 
Type. Detached tooth. / 
Margin of the crown in the median rows of teeth more or less 
acuminate, the apex being either sharp or rounded; the anterior 
face is approximately rhombic in form. 
Form, df Log. Dpper Carboniferous Limestone : Durham, York¬ 
shire, and Derbyshire, in England; Eifeshire and Ayrshire, in 
Scotland. 
P. 613. Fragment described by Owen, loo. cit ., as P. hastingsii ; 
Ticknall, South Derbyshire. Egerton Coll. 
P. 5342. Twenty-five teeth, variously broken and abraded; Tick¬ 
nall. Four of these are shown in PI. I. figs. 4-7, and, as 
all the specimens were obtained from the same bed and 
at the same spot as the type of P. hastingsii , Owen, 
the latter is thus proved to be identical with Agassiz’s 
P. acuminatus. Many of the teeth (e. g. fig. 5) are of the 
same form as the Yorkshire specimens named P. inequi- 
lateralis by Davis. Wilson Coll. 
P. 261. "Worn tooth in matrix; Derbyshire. Purchased , 1880. 
46816-7. Two small teeth and one larger. The latter is consider¬ 
ably broken, hut has a remarkably short root. The small 
teeth are apparently distinguished from those found in 
the Armagh limestone by the relatively greater extent of 
the posterior face of the crown occupied by the basal folds ; 
Derbyshire. Gilbertson Coll. 
P. 2986. Specimen figured in Trans. Roju Dublin Soc. [2] vol. i. 
pi. lix. fig. 24 ; Richmond, Yorkshire. Enniskillen Coll. 
P. 2987. Twelve teeth from the same formation and locality, 
variously broken and abraded. One is of the type of 
u P. ineguilateralis.” Enniskillen Coll. 
P. 1420, P. 1425. Eleven specimens; Richmond. Egerton Coll. 
35472-6, 35478-80, 35482, 36884, 36887, 49612. Twelve speci¬ 
mens ; Richmond. Purchased , 1860, 1862, 1878. 
P. 4899. Three teeth ; Wensleydale, Yorkshire. 
Horne Coll. 
