380 
ACTINOPTERXGII. 
Genus ASTHENOCORMUS, nomen nov. 
Syn. Agassizia , B. Vetter (non Agassiz, 1846, nec Valenciennes, 1847), 
Mittlieil. k. mineral.-geol. Mus. Dresden, pt. iv. 1881, p. 97. 
Trunk elongate. Head relatively large, and snout not produced; 
teeth minute and clustered ; gular plate present. Ossifications in 
sheath of notochord rudimentary or absent. Fin-fulcra absent. 
Pectoral fins large and sickle-shaped, the rays only branching and 
articulated at the extreme end; pelvic fins absent; dorsal in 
advance of the anal fin; caudal fin very deeply forked. Scales 
minute, those of the ventral aspect much broader than deep; 
lateral line inconspicuous. 
Asthenocormus titanms (Wagner). 
1852. Caturus sp., F. A. Quenstedt, Handb. Petrefakt. p. 216. 
1863. JEugnathus titanius , A. Wagner, Abli. k. bay. Akad. Wiss., 
math.-phys. Cl. vol. ix. p. 670. 
1881. Agassizia titania, B. Vetter, Mittlieil. k. mineral.-geol. Mus. 
Dresden, pt. iv. p. 97, pi. iii. 
Type. Nearly complete fish ; Palaeontological Museum, Munich. 
The type species, attaining a length of nearly 2 metres. Length 
of head with opercular apparatus about twice as great as the 
maximum depth of the trunk, and contained somewhat less than 
four times in the total length of the fish. External bones unorna¬ 
mented, exhibiting only their fibrous texture; teeth smooth, many 
acutely pointed and slightly arched; operculum broader than deep. 
Dorsal fin arising at about the middle point of the back; lobes of 
caudal about equal in length to the pectoral fins. Scales all broader 
than deep. 
Form. Sf Log. Lower Kimmeridgian (Lithographic Stone): Bavaria. 
Not represented in the Collection. 
Genus PACHYCORMUS, Agassiz. 
[Poiss. Foss. vol. ii. pt. i. 1833, p. 11.] 
Syn. (?) Saurostomus , L. Agassiz, ibid. 1833, p. 14. 
Cephenoplosus, H. E. Sauvage, Bevue Sci. Nat. vol. ii. 1874, 
p. 428. 
Trunk laterally compressed and irregularly fusiform, relatively 
deep in the abdominal region, very narrow at the extremity of the 
caudal pedicle. Head much less deep than the trunk, the occipital 
region of the cranial roof raised into a large median eminence to 
meet the laterally-compressed dorsal border of the trunk; teeth 
round in section ; suboperculum at least as large as the operculum; 
gular plate present. Ossifications in sheath of notochord absent or 
