SYLL^EMUS. 89 



The only known English species of Syllaemus was originally referred by Dixon 

 to the genus Galamopleurus, which was founded by 'Agassiz on fragments of an 

 entirely different fish from the Upper Cretaceous of Brazil. 1 



1. SyllaBmus anglicus (Dixon). Plate XX; Plate XXI, figs. 1, 2. 



1850. Calamopleurus anglicus, F. Dixon, Geol. Sussex, p. 375, pi. xxxii, figs. 11, 12. 

 1888. Galamopleurus anglicus, A. S. Woodward, Proc. Geol. Assoc, vol. x, p. 324. 

 1901. Sylliemus anglicus, A. S. Woodward, Catal. Foss. Fishes B. M., pt. iv, p. 351. 



Type. — Head and abdominal region, probably from zone of Eolaster plarms ; 

 British Museum. 



Specific Characters. — A large and robust species attaining a length of about 

 45 cm. 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 maxilla ; anterior margin of 

 preoperculum 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; dorsal fin arising at a distance 

 from the occiput equal to the total length of the skull. About 8 or 10 transverse 

 series of scales in advance of the dorsal fin, each with approximately 1 2 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. 



Description of Specimens. — The type specimen in the Egertou Collection exhibits 

 the imperfectly preserved head and abdominal region, and is shown of the natural 

 size from the left lateral aspect in PL XX, fig. 1. It displays the long, pointed 

 form of the head, the proportions of the jaws, the upper teeth, the rounded shape 

 of the trunk, the characters of the scales, and the position of the pectoral, pel vie, 

 and dorsal fins. The complete length of the fish, with its forked caudal fin, is 

 indicated only by two known specimens, one from an undetermined zone at 

 Shalford, near Guildford (PI. XX, fig. 2), the other from a Turonian zone near 

 Dunton Green, Kent (W. J. Lewis Abbott Collection). These three specimens 

 together exhibit the form and proportions of the species rioted in the diagnosis. 



The head is laterally compressed and deeper than broad, with a rather acute 

 but not produced rostrum. The cranium is well ossified, and its flattened roof 



1 Calamoplcurus cyliudricus, L. Agassiz, Ediub. New Phil. Journ., vol. \\\. 1841, p. 84; A. S. 

 Woodward, Catal. Foss. Fishes B. M., pt. iii, 18t»5, p. 499. 



12 



