ICHTH Y 0 TOMI. 
4 
It is uncertain at present whether all the specimens commonly 
referred to this species are truly identical, but we venture to adopt 
the provisional arrangement of Kner. Many of the differences 
noted between the various fossils are undoubtedly due to accident 
in preservation; moreover, it appears that errors in description must 
also be taken into account 1 . 
Form, Loc. Lower Permian (Rothliegendes) : Bohemia, Silesia, 
Rhenish Prussia. 
19665-6. Two imperfect skeletons, one showing a portion of the 
spine in position, the other a part of the pectoral fin ; 
Ruppersdorf, Bohemia. The first of these specimens 
exhibits distinct calcifications in the sheath of the noto¬ 
chord, and is referred to by Hasse, Neues Jahrb. 1883, 
vol. ii. p. 65. Purchased , 1845. 
35015. Imperfect skeleton, with the impression of the complete 
spine and a well-preserved fragment of this defence 
(PI. YI. fig. 1) ; Ruppersdorf. This specimen exhibits 
complete broad ring-like calcifications in the sheath of the 
notochord in the caudal region, and is noticed by Hasse, 
loc. cit. Purchased , 1860. 
P. 1729. Crushed skull and pectoral arch, with the spine in position ; 
Ruppersdorf. Egerton Coll. 
P. 3182. A similar, but smaller specimen ; Ruppersdorf. 
Enniskillen Coll. 
38154. Specimen 0*325 m. in length, showing imperfect teeth and 
spine, a portion of the pectoral arch, the vertebral column, 
and impressions of the dorsal and pectoral fins ; Braunau, 
Bohemia. In the abdominal region there appear to be 
calcifications in the sheath of the notochord. The acutely- 
lobate character of the pectoral fin is well shown by the 
preservation of a fringe of horny fin-rays, such as are also 
present in the dorsal fin. 
Presented by Sir Roderick I. Murchison , K.C.B., 1864. 
P. 3183. Portion of axial skeleton of the trunk, with median fin, 
doubtfully referred to this genus and species; Braunau. 
The expansion of the bases of the neural and haemal arches 
is well shown. Enniskillen Coll. 
1 E. g. see Kner’s remarks upon the spine described by Groldfuss, loc. cit. 
p. 550. 
