PLATYSOMATIDiE. 
529 
anterior border ; principal flank-scales much deeper than broad, 
with large peg-and-socket articulation; dorsal and ventral scales 
somewhat broader than deep, with well-defined inner keel, but no 
peg-and-socket; scales of upper caudal lobe acutely lozenge-shaped. 
Well-developed ridge-scales present only upon the caudal pedicle 
and upper caudal lobe. 
Eurynotus crenatus, Agassiz. 
1835. Eurynotus crenatus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. p. 154, 
pis. xiv. a, b. 
1835. Eurynotus Jimhriatus , L. Agassiz, ibid. p. 157, pi. xiv. c. figs. 1-3. 
[Portions of trunk ; Oxford Museum.] 
1835. Eurynotus crenatus, S. Hibbert, Trans. Roy. Soc. Edinb. vol. 
xiii. pi. vii. fig. 4. 
1844. Plectrolepis ruyosus, L. Agassiz, tom. cit. p. 306 (name only). 
1850. Plectrolepis ruyosus, Sir P. Egerton, Quart. Journ. Geol. Soc. 
vol. vi. p. 4. [British Museum.] 
1854. Platysomus declivus, J. Morris (ex Agassiz, MS.), Cat. Brit. Foss, 
ed. 2, p. 339 (name only). [Distorted fisli; British Museum.] 
1867. Eurynotus Jimhriatus, R. H. Traquair, Trans. Roy. Soc. Edinb. 
vol. xxiv. p. 710, pi. xiv. figs. 8, 9. 
1879. Eurynotus crenatus, R. H. Traquair, ibid. vol. xxix. p. 349, pi, iij. 
figs. 1-16. 
1881. Eurynotus crenatus , R. H. Traquair, ibid. vol. xxx. p. 54. 
1890. Eurynotus crenatus, R. H. Traquair, Proc. Roy. Soc. Edinb, 
vol. xvii. pp. 392, 400. Q 
Typ>e. Imperfect fishes ; Edinburgh Museum (in part). 
The type species, attaining a length of about 0*25-0-3. Maxi¬ 
mum depth of trunk equalling about one-third of the total length ; 
the dorsal contour angulated at the origin of the dorsal fin, the 
ventral contour gently arched. Head and opercular apparatus 
small, occupying scarcely more than one-sixth of the total length ; 
external bones ornamented with coarse striae, often concentric; 
maxilla elongated, irregularly triangular, somewhat more than 
twice as deep behind as in front, the majority of its superficial 
striations vertical. Fin-rays and fulcra robust and smooth, the 
rays of the dorsal sometimes serrated posteriorly ; pectoral fins 
more than twice as large as the pelvic pair, as deep as the anterior 
portion of the dorsal ; anal fin deeper than long, terminating ojipo- 
site the hinder extremity of the dorsal. Scales of moderate size, 
those of the anterior portion ornamented with delicate oblique striae 
terminating in the posterior serrations, the striae becoming obsolete 
towards the caudal region. 
PAET 11. 
Z M 
