198 
ACTINOPTERYGII. 
Vomerine teeth, in five, and splenial teeth 
in four regular longitudinal series; 
scales covering whole of trunk, and 
none united with jagged sutures .... 
Vomerine teeth in live, and splenial teeth 
in three regular longitudinal series; 
squamation confined to region in 
advance of median tins: caudal fin 
scarcely forked. 
Oral surface of vorneir convex from side to 
side, and teeth in five regular longi¬ 
tudinal series; splenial teeth in three 
series, the outer sometimes in part 
subdivided, the inner sometimes 
irregularly supplemented; squamation 
confined to region in advance of 
median fins . 
(c.) Splenial dentition comparatively degene¬ 
rate, restricted to a space well within 
outer margin, and number of longitu¬ 
dinal series inconstant ; no dermal 
spines. 
Vomerine teeth irregular, in from three to 
five longitudinal series; squamation 
confined to region in advance of 
median fins . 
(di) Abnormal genera with median occipital 
spine, and more or less spinous pectoral 
arch. 
Vomerine teeth apparently in five, and 
splenial teeth in three regular longi¬ 
tudinal series ; clavicular spines large ; 
scales wanting. 
Imperfectly known, but greater portion of 
trunk covered with large, rhombic, 
keeled scutes ... 
II. Neural and haemal arches of axial skeleton 
of trunk expanding and completely encir¬ 
cling the notochord. 
Vomerine teeth in five, and splenial teeth in 
three regular longitudinal series; caudal 
pedicle very short, and fin fan-shaped ; 
squamation variable .. 
Dentition as in Palceobalistum ; caudal pedicle 
slender and fin slightly forked ; squama¬ 
tion confined to region in advance of 
median fins . 
Gyrodus (p. 233). 
Stemmatodus (p. 248). / 
Coelodus (p. 249). - 
Anomceodus (p. 258). 
Coccodus (p. 266). 
Xenopholis (p. 269). 
Palceobalistum (p. 270). 
Pycnodus (p. 275). / 
