﻿438 ACTTNOPTERTGTT. 



1833. Amblypterus lateralis, L. Agassiz, ibid. pp. 4, 39, pi. iv. figs. 1, 



7-9. [Strassburg Museum.] 

 1857. Amblypterus latus, F. H. Troschel, Verhandl. naturh. Verein. 



preuss. Rheinlande u. Westphalens, p. 13, pi. ii. fig. 17. 

 1877. Amblypterus lotus, ~R. H. Traquair, Quart. Journ. Geol. Soc. vol. 



xxxiii. p. 552, and Ganoid Fishes Brit. Carb. Form. (Pal. Soc), 



pi. ii. fig. 1. 

 1877. Amblypterus lateralis, R. H. Traquair, Quart. Journ. Geol. Soc. 



vol. xxxiii. p. 552. 



Type. Nearly complete fishes ; Strassburg Museum. 



The type species. Trunk regularly fusiform, the caudal pedicle 

 being short and robust; dorsal contour much arched, and maximum 

 depth in advance of the dorsal fin contained slightly more than three 

 times in the total length. Head and opercular apparatus small, 

 scarcely occupying one quarter of the total length ; external bones 

 striated. Fins relatively large, the pelvic pair smaller than the 

 pectorals, arising midway between the latter and the anal ; dorsal 

 and anal fins longer than deep, the dorsal arising behind the middle 

 point of the back, and the anal opposed to its hinder two thirds. 

 Scales large and smooth, those of the middle of the flank not mnch 

 deeper than broad. 



The sole differences between this species and the so-called A. 

 lateralis seem to the present writer to be due to differences of age 

 and the state of preservation. There are sparse striations upon the 

 head-bones of all well-preserved specimens, and no constant 

 difference in the proportions of the scales can be observed in the 

 collection recorded below. 



Form. Sf Log. Lower Permian : Rhenish Prussia. 



22658. Crushed remains of an adult individual, about 0-18 in length, 

 in counterpart ; Lebach. Purchased, 1848. 



22658 a. Well-preserved specimen, in counterpart, showing the 

 subdivision of each series of scales at the base of the 

 dorsal fin into two series ; Lebach. Purchased, 1848. 



29006. A fine example in counterpart, measuring 016 from the 

 extremity of the snout to the base of the upper caudal 

 lobe ; Lebach. The squamation aud portions of the fins 

 are well shown. Purchased, 1859. 



P. 979, P. 3458. Two well-preserved specimens in counterpart, and 

 the greater portion of a large individual with traces of 

 the fine dentition ; Lebach. 



Egerton Sf EnnisTcillen Colls. 



