578 
ACTINOPTERYGII. 
Type. Hinder half of cranium ; British Museum. 
The type species, with skull about 0'1 in length and O' 05 in 
maximum width. Two upper prcopercular spines inconspicuous. 
Form, ij- Loc. Lower Eocene (London Clay) : Sheppey, Kent. 
P. 9432. Well-preserved postorbital portion of cranium, the type 
specimen figured by Kdnig. The two median frontal 
ridges are shown. Old Collection. 
35719. Remains of head displaying the right preoperculum, which 
is shown, nat. size, in the accompanying fig. 21 a. The 
Fig. 21. 
Amptieristm toliapicus-, right preoperculuin, outer aspect (A), and binder 
portion of cranium, upper aspect (B), nat. size, epo., epiotic ; /•> facettes , 
fr., frontal ; orb., orbit ; pto., pterotic ; s.occ., eupraoccipital ; x., equa 
mosal (?) ; 1-4, ridges. 
lowermost spine is broken, and the upper end of the bone 
is incomplete. A ridge and facette (/) indicate the 
attachment of the bony suborbital stay. Purchased, 1800- 
P. 630. Fragmentary head and three anterior vertebral, labelled by 
Agassiz and Egerton as intended to be the type spccimi n 
of Oonioynathus coryphasnoid.es. Egerton Col . 
35718. Imperfect head. Purchased, I860. 
P. 9433-35. Three imperfect heads, one showing 8 pairs ot 
branchiostegal rays. History unknown. 
38899. Remains of head. Bowerbank Coll. 
P. 4143, P. 4540. Five imperfect specimens, the first showing tb c 
frontal ridges, as represented in the accompany 
