134 ACTIlS’OrTEEYGn. 
Halecopsis insignis (Delvaux & Ortlieb). 
1844. Halecopsis Icevis, L. Agassiz, Poiss. Foss. vol. v. pt. ii. p. 139 
(name only). 
1887. Osnieroides insignis, E. Delvaux & J. Ortlieb, Ann. Soc. Geol. 
Belg. vol. xiv. Mem. p. 74, pi. iii. figs. 2-7, 10, 11. 
1888. Osmeroides msignis, E. Delvaux & J. Ortlieb, Ann. Soc. Geol. 
Nord, vol. XV. p. 60, pis. i., ii. 
Tyjpe. Imperfect fish ; Delvaux Collection. 
The type species, attaining a length of about 0*3. Length of 
head with opercular apparatus contained about four and a half 
times, maximum depth of trunk five times in the total length of the 
fish to the base of the caudal fin. Extent of dorsal fin equalling 
about two thirds the depth of the trunk at its insertion; extent 
of anal fin only one third that of the dorsal. 
Form. Log. Lower Eocene: Chievres, near Ath, Belgium 
(Ypresian Formation) ; London Basin (London Clay). 
43116, 43119. Two specimens displaying remains of the hinder 
portion of the head and part of the abdominal region, the 
second much the smaller ; London Clay, Primrose Hill, 
London. The expanded preoperculum is shown in each, 
with traces of radiating branches from the slime-canaL 
In the large fossil the slime-canal is also shown with 
short branches on the postorbital cheek-plates. In the 
smaller fossil the upper aspect of the supraoccipital is- 
exposed; and the frontal seems to extend downwards in 
a small plate on each side in front of the otic region. 
Weilierell Coll. 
41721. Imperfect head and anterior scales ; London Clay, Sheppey. 
Touhnin Smith Coll. 
28713a. Branchial region with remains of vertebrae and scales; 
London Clay, Sheppey. Purchased, 18.53. 
P. 1747. Nine fragmentary specimens of head and scales; London 
Clay, Sheppey. Egerton Coll. 
P. 3845. Hine similar specimens ; London Clay, Sheppey. 
^nnislcillen Coll. 
• • 
41409. Abraded specimen ; Bed Crag (derived from London Clay), 
Suffolk. Purchased, 1869. 
