PERCID.E. 
517 
decreasing in length ; posterior dorsal relatively low, with 
short spine and 8 articulated rays ; anal with 3 short 
spines and 7 articulated rays ; caudal fin forked. Scales 
very small. Egerton 4' Enniskillen Colls. 
P - 3912. Nearly similar Percoid 0-105 in length, with 11 articulated 
rays in posterior dorsal and 8 articulated rays in anal 
fin, and caudal fin rounded; Lower Oligocene, Aix-en- 
Provence. Enniskillen Coll. 
Genus MIOPLOSUS, Cope. 
[Bull. U.S. GeoL Surv. Territ. vol. iii. 1877, p. S13.J 
Prunk laterally compressed and elongate-fusiform. Articulation 
’’f mandible beneath hinder border of orbit, and all teeth very 
small ; ascending limb of preoperculum smooth, lower limb coarsely- 
serrated ; operculum rounded, without spines. \ ertebrae 10 or 1 i 
■n abdominal, 14 or 15 in caudal region. Two dorsal fins, the 
anterior with 9 spines, the posterior with 1 spine and 12 to 14 
articulated rays ; anal fin with 2 spines and 10 to 14 articulated 
f ays ; caudal fin slightly forked. Scales finely serrated. 
An extinct North-American freshwater Eocene genus. 
Mioplosus labracoides, Cope. 
1877. Mioplosus labracoides, E. D. Cope, Bull. U.S. Geol. Surv. Ternt. 
vol. iii. p. 814. 
1884. Mioplosus labracoides , E. D. Cope, \ ert. Pert. Form. W est, 
Book I. (Hep. U.S. Geol. Surv. Territ. vol. iii.), p. 89, pi. xn. 
fig- 1. 
S' ype. Nearly complete fish; National Museum, Washington. 
•f be type species, attaining a length of about 0-35. Maximum depth 
trunk about equalling length of head with opercular apparatus, 
and contained four times in total length of fish. Third dorsal fin- 
s pine longest ; 12 articulated rays in dorsal, 14 in anal fin. 
Eo>-m. 4 - Loc. Eocene (Green ltiver Shales) : Wyoming, U.S. A. 
p - 5217. Slightly- distorted specimen 0-25 in length. 
Presented by Lord Avebury, 1886. 
P - 7492. Larger, more distorted specimen. Purchased, 1895. 
The following species, all except the fourth from the Green ltiver 
Shales of Wyoming, have also been distinguished, but only dificr 
r ery slightly from the type species : — 
