314 
ACTINOPTERYGII. 
t 
enlarged. As the series are traced backwards the peg- 
and-socket articulation gradually disappears, while the 
inner rib widens and is finally indistinguishable. 
Enniskillen Coll. 
The following species have also been imperfectly defined, but do 
not appear to be represented in the Collection : — 
Heterolepidotus angulati , W. Deecke, Mittheil. Comm. geol. 
Landes-Untersuch. Elsass-Lothr. vol. i. (18881, p. 207.— 
Lower Lias; Buchsweiler, Alsace. [Nearly complete 
trunk with hinder portion of head ; Geological Survey 
Museum, Strassburg.] 
Heterolejpidotus (?) leptocephalus : Semionotus leptocephalus , L. 
Agassiz, Neues Jahrb. 1832, p. 145, and Poiss. Foss, 
vol. ii. pt. i. pp. 8, 222 (1833-44), pi. xxvi. fig. 1 ; 
F. A. Qnenstedt, Flcizgeb. Wiirttemb. (1843), p. 243; 0. 
Fraas, Wiirtt. Jahresh. 1861, p. 83.— Upper Lias; Poll, 
Wurtemberg. [Nearly complete fish; unknown.] 
Heterolepidotus minor , J. AV. Davis, Proc. Yorksh. Geol. & Polyt. 
Soc. n. s. vol. viii. (1883), p. 403, pi. xxii.—Lower Lias ; 
Lyme Fegis. [Fish too imperfect for specific definition; 
J. AV. Davis Collection, Halifax.] 
A fish closely resembling Heterolepidotus but differing in not 
having the tail forked, is known from the Lower Oolite of Brora, 
Sutherland. It is believed to have been obtained from the carbon¬ 
aceous shale underlying the main seam of lignite in Strath Brora, 
and the original specimens are now in the Duke of Sutherland's 
Museum at Dunrobin Castle. The fish has been described under 
the name of Semionotus joassi (A. S. Woodward, Ann. Mag. Nat. 
Hist. [5] vol. xx. 1887, p. 179, pi. viii.), but its generic position 
must still be regarded as undetermined (W. Deecke, Paleeontogr. 
vol. xxxv. p. 103). The detached maxilla ascribed to it ( loc . cit. 
pi. viii. fig. 3) is probably named erroneously, and seems to belong 
to a Paheoniscid. 
A generically indeterminable portion of squamation which may 
belong either to the Palmoniscidas or to a fish resembling Eugnathus 
and Heterolepidotus is described as follows :— 
Crenilepis sandbergeri, AY. Dames, Palaeont. Abhandl. vol. iv. 
Y2e<C* /Sty (1888), p. 170, pi. xv. fig. 3.—Muschelkalk ; Krainbcrg, (J7T &^ 
^ . ‘ near 'Wurzburg. [Abdominal fiank-squamation; L T niver- 
C. s /?3?f r isk l -/5 
sity of AViirzburg. 
