412 
ACTTNOPTEETGIT. 
P. 1939, ?. 1942, P. 3936 b, P. 3938. Two fine specimens in 
counterpart, and a more imperfect fish, all labelled by 
Agassiz. Eyerton ^ Enniskillen Colls. 
P. 9445. Pish 0’09 in length, in counterpart. Purchased. 
P. 1939 a, P. 3936 a. Two small specimens from the Gazola 
Collection. Eyerton Enniskillen Colls. 
P. 5135. Two imperfect small specimens. 
Presented hy Mrs. M. E. Fort, 1886. 
The following specimens are too imperfect for determination, but 
the first was referred to 2Iyri^ristis by Agassiz;— 
P. 644-a. Two imperfect heads with opercular apparatus, the first 
intended to be the type specimen of Myripristis toliapicus, 
Agassiz, recorded by name only in Pep. Prit. Assoc. 1844 
(1845), p. 307; London Clay, Sheppey. The incomplete 
cranium in the second specimen seems to be quite different 
from that of Myripristis. Eyerton Coll. 
' it /'■) J 
Genus HOLOCSNTRUM (Artedi), Cuvier. 
[Eegne Animal, ed. 2, vol. ii. 1829, p. 150.] 
Trunk more or less elongated and laterally compressed. Frontal 
region of skull gently rounded, not ridged; cleft of mouth small, 
mandible not prominent, and teeth minute. Opercular bones and 
suborbitals serrated; operculum with two spines; angle of pre¬ 
operculum produced into spine. Vertebrae 10 or 11 in the abdominal, 
15 or 16 in the caudal region. Pelvic fins with one spine and 
7 divided rays, arising behind the origin of the pectorals. Dorsal 
fin much extended, divided into two portions, the foremost spinous ; 
anal fin not much extended, with 4 spines, of which the third is 
relatively stout and long; caudal fin deeply cleft. Scales large and 
ctenoid, more or less uniform. 
A figure of the skeleton of an existing species of this genus is 
given by Agassiz, Poiss. Loss. vol. iv. pi. P. fig. 1. The existing 
species live at the surface of tropical seas. 
Holocentrum macrocephalum, Plainville. 
1796. ILolocentrus soyo, G. S. Volta, Ittioht. Veron. p. ccx. pi. li. fig. 2 
(errore). 
1796. Chcetodon saxatilis, G. S. Volta, ibid. p. cclxv. pi. Ixiv. fig. 1 
{errore ). 
