324 
ACTINOPTERYGII. 
depth of the trunk, and occupying about one-quarter of the total 
length of the fish. The ornament of the external bones consisting 
of closely arranged prominent ridges ; the scales with strongly 
marked longitudinal ridges and furrows terminating in posterior 
denticulations, and with some conspicuous vertical folds at the 
anterior border. 
Form. Q Log. Upper Trias : Baibl, Carinthia. 
P. 5958. A typical specimen wanting all the fins except the dorsal 
and caudal, but displaying the squamation. 
Purchased. 1889. 
Ptycholepis marsh!, Newberry. 
1878. Ptycholepis marshii, J. S. Newberry, Ann. New York Acad. Sci. 
vol. i. p. 127. 
1888. Ptycholepis marshii, J. S. Newberry, Foss. Fishes Trias, N. 
Jersey & Connecticut (Mon. U.S. Geol. Surv. no. xiv.), p. 66, 
pi. xix. figs. 1, 2. 
Type. Nearly complete fish; 7?^/."^>^1 
A species of slender proportions, attaining a length of about 0*2. 
Head with opercular apparatus occupying somewhat less than one- 
quarter of the total length of the fish. Ornamental rugae on cranial 
roof slightly radiating; those of the facial and opercular bones 
more or less parallel and forked. Dorsal fin far forwards, and 
pelvic fins arising opposite its hinder extremity. Scales exhibiting 
only longitudinal ridges and furrows, and the hinder border often 
deeply serrated. (Newberry.) 
Form. Sf Log. Trias : Durham, Connecticut, U.S.A. 
Not represented in the Collection. 
Some detached scales from the Upper Trias of Desano, Lombardy, 
are also named Ptycholepis barboi by F. Bassani, Atti Soc. Ital. Sci. 
Nat. vol. xxix. (1886), p. 38. /? 
The so-called Ptycholepis tenuisquamata (B. Ivner, Sitzungsb. k. 
Akad. Wiss., math.-naturw. Cl. vol. lvi. pt. i. 1867, p. 913, pi. iv.) 
from the Upper Trias of Baibl, Carinthia, apparently does not belong 
to this genus. 
Genus OSTEORACHIS, Egerton. 
[Quart. Journ. Geol. Soc. vol. xxiv. 1868, p. 500.] 
Syn. Isocolum, Sir P. Egerton, ibid. 1868, p. 501. 
Harpactes, Sir P. Egerton (non Templeton, 1834), Geol. Mag. [2] 
vol. iii. 1876, p. 441. 
Harpactira, Sir P. Egerton, ibid. 1876, p. 576. 
Trunk elongate. External bones ornamented with tuberculations 
or rugae; marginal teeth relatively large and well-spaced ; splenial 
