378 
ACTIXOPTERTGII. 
1818. Centriscus aculeatus, H. D. de Blainville, Nouv. Diet. d’Hist. 
Nat. vol. xxvii. p. 389. 
1835. RJiamphosus aculeatus, L. Agassiz, Neues Jahrb. p. 291 (name 
1839-42. R^amphosus aculeatus, L. Agassiz, Poias. Foss. vol. iv. 
p. 270, pi. xxxii. fig. 7. 
1888. RhampJiosus aculeatus, L. Vaillant, Exped. Scient. Travailleur 
et Talisman—Poissons, p. 339. 
1898. RhampTiosus aculeatus, F. Bassani, Paleeontogr. Italica, vol. iii. 
p. 82, pi. ix. fig. 4. 
Type. Imperfect fish ; Museum of Natural History, Paris. 
The type species, attaining a length of about 0*12. Proportions 
somewhat uncertain owing to imperfection of few known specimens ; 
but snout extremely attenuated, the length of the head with oper¬ 
cular apparatus probably equalling that of the trunk from the 
pectoral arch to the base of the caudal fin, also about equalling the 
length of the dorsal fin-spine, which bears posterior denticulations. 
Probably 8 abdominal vertebrae, and 14 caudals. Dorsal and anal fins 
equal and directly opposed, each with 9 rays. Scales very minute. 
Form. Loc. Upper Eocene : Monte Bolca, near Verona. 
P. 5125. Small specimen wanting caudal fin and with dorsal spine 
imperfect. Purchased, 1886. 
Rhamphosus biserratus, Bassani. 
1876. Rhamphosus hiserratus, F. Bassani, Atti Soc. Veneto-Trent. Sci. 
Nat. vol. V. p. 151, pi. ii. fig. 3. 
Type. Imperfect fish ; Geological Museum, University of Padua. 
Bather larger than the type species, with comparatively short 
and stout spine, the length-of this apparently not greater than the 
depth of the trunk at its insertion. 
Form, df Loc. Upper Eocene: Monte Bolca. 
Not represented in the Collection. 
Genus AMPHISIUB (Klein), Cuvier. 
[Begne Animal, vol. ii. 1817, p. 350.] 
Trunk oblong and much laterally compressed, with very small 
caudal region curved downwards. About 6 large and elongated 
abdominal vertebrae, 14 very small caudals. Pelvic fins rudi¬ 
mentary, well behind the pectorals ; caudal fin rounded. Bony 
plates dorsally and ventrally in abdominal region, the dorsal armour 
intimatelv connected with the endoskeleton ; no scales. 
Existing species of this genus occur in the shallow seas of the 
tropics from the eastern coast of Africa to China. 
