﻿378 cBossopnraYGii. 



28863. Remains of fish, 0*27 in length, ventral aspect. 



Purchased, 1854. 



P. 827, P. 3293. Crushed trunk of fish, wanting head and paired 

 fins. Egerton Sf Enniskillen Colls. 



P. 827 a, P. 3293 a. Portions of head and anterior scales of a large 

 individual : a close uniform series of conical teeth is seen 

 in the mandible. Egerton Sf Enniskillen Colls. 



Under the preoccupied generic name of Gyrolepis, and with the 

 specific name of G. posnaniensis, scales much resembling those of 

 the foregoing genera, from Lower Palaeozoic boulders near Meseritz, 

 Silesia, are described by G. Kade, Programm k. Eealschule zu 

 Meseritz, 1858, pp. 17, 18, figs. 8-10. 



Genus MEGALICHTHYS, Agassiz. 

 [Poiss. Foss. vol. ii. pt. ii. 1844, pp. 89, 154.] 



Syn. Centrodus, F. M'Coy, Ann. Mag. Nat. Hist. [2] vol. ii. 1848, p. 3, 



and ibid. vol. iii. 1849, p. 140. 

 Parabatrachus, R Owen, Quart. Journ. Geol. Soc. vol. ix. 1853, 



p. 67. 

 Phomboptychius, J. Young {ex Huxley, MS.), Quart. Journ. Geol. 



Soc. vol. xxii. 1866, p. 604. 

 Ganolodus, E. Owen, Trans. Odontol. Soc. vol. v. 1867, p. 354 



(in part). 

 Ectosteorhachis, E. D. Cope, Proc. Amer. Phil. Soc. vol. xix. 

 1880, p. 56. 



Cranial roof-bones in advance of the parietals rarely fused into a 

 continuous shield, without a median frontal foramen ; an anterior 

 azygous jugular plate present. Teeth rounded in transverse section. 

 Ossified vertebrae in the form of narrow rings. First dorsal fin 

 nearly opposite to the pelvic pair, and the second dorsal opposed to 

 the anal. Tail intermediate between the diphycercal and hetero- 

 cercal stages. Scales more or less smooth and punctate. 



Megalichthys hibberti, Agassiz. 

 [Plate XIII. fig. 4.] 



1835. Ichthyolithus clackmannensis, J. Fleming, Edinb. New Phil. 

 Mag. vol. xix. p, 314, pi. iv. figs. 1-3. [Portions of Fish ; Edin- 

 burgh Museum.] 



1844. Megalichthys hibberti, L. Agassiz, Poiss. Foss. vol. ii. pt. ii. 

 p. 90, pis. lxiii., lxiii. «., lxiv. 



