CROSSOG^^ATHID^. 
351 
Trank subcylmdrical, not much laterally compressed ; head and 
opercular region compressed to a sharp edge below. Cranial roof 
slightly arched from side to side, with a shallow rhombic median 
depression in the frontal region. 
Syllaemns latlfrons, Cope. 
1875. Syll(Bmus latifrom, E. D. Cope, op. cit. p. 181. 
Type, imperfect head and abdominal region. 
The type species, probably attaining a length of about 0“3. 
Length of head with opercular apparatus considerably exceeding 
the maximum depth of the trunk, and probably contained about 
three and a half times in the total length to the base of the caudal 
fin. Nine transverse series of scales in advance of the dorsal fin ; 
all scales quite smooth. 
Form. Log. Upper Cretaceous ; Pike’s Peak, Colorado. 
Not represented in the Collection. 
Syllsemus anglicus (Dixon). 
1850. Calamopleurus anglicus. F. Dixon, Geol. Sussex, p. 375, pi. xxxii. 
figs. 11,12. ^ 
1888. Calamopleurus anglicus’, A. S. Woodward, Proc. Geol. Assoc, 
vol. x. p. 324. 
Type. Head and abdominal region ; British Museum. 
A large and robust species, attaining a length of about 0-45. 
Length of head with opercular apparatus scarcely exceeding the 
maximum depth of the trunk and contained slightly more than 
four times in the total length to the base of the caudal fin. A 
narrow border of very fine granulations immediately above the 
teeth on the outer face of the premaxilla; anterior margin of 
prebperculum much thickened, especially at the angle, from which 
numerous undulations, almost ridges, radiate; operculum smooth. 
Pectoral fins long and narrow, with about 14 rays ; pelvic fins with 
8 rays, the foremost stoutest, arising much nearer to the caudal 
than to the pectoral fins ; a»terior dorsal, with not less than 8 rays, 
arising at a distance from the occiput equal to the total length of 
the skull. ^ About eight or ten transverse series of scales in advance 
of the anterior dorsal fin, each with approximately twelve scales on 
either side ; the scales when abraded exhibiting traces of very fine 
parallel or slightly radiating lines directed antero-posteriorly in 
the exposed area. 
This fish cannot belong to the genus Calamopleurus^ which was 
founded on fragments from the Upper Cretaceous of Brazil, with 
u 
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