EUGXATHID.E. 
307 
and there are indications of a similar series of perforated 
scales on the dorsal portion of the flank, extending as far 
backwards as the dorsal fin. One of the pelvic basal bones 
is exposed. Egerton Coll. 
P. 6423. Distorted and partly imperfect specimen about 0*5 in 
length. The teeth of the dentary bone are very closely 
arranged. Beckles Coll. 
P. 1538. Imperfect remains of head and greater portion of trunk of 
a similar fish. The biserial fulcra are well shown on the 
right pelvic fin. Egerton Coll. 
P. 2011. Trunk with median fins. Egerton Coll. 
P. 2010. Small specimen about 0‘36 in length, The head is much 
crushed, and parts of the fins are wanting. Egerton Coll. 
P. 1542. Remains of small specimen originally about 0*3 in length. 
The head-bones are much displaced, so that several internal 
elements are shown. The paired fins are preserved, and 
the greater part of the flank-squamation is exposed from 
within. Egerton Coll. 
P. 3620. The type specimen of the so-called Semionotus rhombifer 
described by Agassiz, loc. cit., being a fish somewhat 
smaller than the preceding and almost certainly the young 
of Heterolepiclotus latus. The comparative smoothness of 
the head-bones and post-clavicular plates is apparently 
due to imperfect preservation. Enniskillen Coll. 
P. 1538 b. Middle portion of trunk of a similar fish. Egerton Coll. 
P. 1538 a. Caudal region of another small specimen. Egerton Coll. 
Heterolepidotus serrulatus (Agassiz). 
1843-44. Lepidotus serrulatus , L. Agassiz, Poiss. Foss. vol. ii. pt. i. 
p. 305, pi. xxxi. 
1868. Eulepidotus serrulatus, Sir P. Egerton, Quart. Journ. Geol. Soc. 
vol. xxiv. p. 505. 
1872. Heterolepidotus serrulatus, Sir P. Egerton, Figs. & Descript. Brit. 
Organic Remains, dec. xiii. (Mem. Geol. Surv.), no. 2, p. 2. 
1890. Eugnathus serrulatus, Woodward & Skerborn, Catal. Brit. Foss. 
Vertebrata, p. 79. 
Type. Fish wanting caudal extremity ; British Museum. 
A species nearly equalling H. latus in size, but differing in its 
relatively larger and smoother scales, and in the robustness of the 
x 2 
