494 
ACTINOPTERYGII. 
figs. 2, 3, pi. xxix. fig. 1. The drawing given by Agassiz 
is very unsatisfactory, and the remarkable bony gill- 
rakers, with the compound first vertebra and the anterior 
portion of the right dentary, are re-figured by the present 
writer. The large and broad ascending process of the 
dentary behind its tooth-bearing margin is well seen; 
and the ceratohyal supports slender, widely-spaced bran- 
chiostegal rays. Enniskillen Coll . 
21974. Imperfect cranium and chain of thirteen anterior vertebrae, 
exposed from the left side. The first vertebral centrum, 
as in the previous specimen, appears to consist of two 
fused discs, the hinder alone bearing the rib-facette. 
(fee*, fveff A s.w. iqicj' foj?>o . Purchased , 1848. 
36083. Left dentary bone as large as that of the type specimen of 
0. vectensis, shown from the outer aspect. The depth at 
the symphysis seems to be about the same in the two 
specimens, but the distance from the symphysis to the 
hinder margin of the ascending process is much the least 
in the present fossil. Cunnington Coll. 
As.k/. /y/y,/./J/, JJP. fy . 
P. 1121. Fragment of small vertebral column, described and partly 
figured by the present writer, loc. cit. p. 349, pi. xxviii. 
fig. 4. Egerton Coll. 
23407, 36082. Two portions of much larger vertebral column. 
Purchased , 1849, and Cunnington Coll. 
50090. Anterior portion of very large vertebral column, and some 
head-fragments. Purchased , 1879. 
24816. Detached vertebral centrum pierced by a mesial foramen 
for the passage of a remnant of the notochord. 
Cunnington Coll. 
OEONOSCOPUS, Costa. 
[Ittiol. Foss. Ital. 1853, p. 2 ( Ionoscopus ).] 
Syn. Attakeopsis , V. Thiolliere, Bull. Soc. G6ol. France, [2] vol. xv. 
1858, p. 784 (name only), and Poiss. Foss. Bugey, pt. ii. 
1873, p. 22. 
Macrorhipis , A. Warner, Abh. k. baw Akad. Wiss., math.-phvs. 
Cl. vol. ix. 1863, p. 723. 
Head large and snout pointed; maxilla much deepened behind, 
with nearly straight dentigerous border; teeth of moderate size, 
stout and conical or styliform. Vertebral centra usually about as 
