﻿POSITION OF THE PALtFONISCID^E. 



37 



ever, in discussing the affinities of C/ieirolepis, Professor Huxley alludes to its resem- 

 blance to Palceoniscus, which he considered as a form connecting it " with that large body 

 of fossil fishes which have more or less direct relations with Lepidosteus." Cheirolepis, 

 though still retained as the type of a special family as proposed by H. Miller and by 

 Pander, was therefore referred by Professor Huxley, though with a little doubt, to the 

 sub-order Lepidosteidae. 



In the paper " On the Affinities of Platysomus and Allied Genera," in which 

 Professor Young proposed to institute a new sub-order of Ganoids, that of the 

 " Lepidopleuridcs," to include the Pycnodonts and Platysomids, reference is made to the 

 position of Amblypterus as being " among the Lepidosteidce, not far from Oxygnathus" 

 as shown by its cranial anatomy and dentitional characters. 1 



By Dr. Lutken the Ganoidei are classed as follows, merely as part of the Teleostei or 

 Bony Fishes : 2 



b. Pycnodontes. 



c. Crossopteri. 



y. Sturiones. 



Dr. Martin also places the Palaoniscida with the Lepidosteidce or " Euganoidei," the 

 latter term having been first proposed by Lutken. Of the other " Euganoidei " he 

 considers Pholidophorus to bear the most resemblance to Palaoniscus. The genera, 

 which he includes in the family Palaotiiscidte, are : — Palceoniscus, Acrolepis, Ambly- 

 pterus, Pygopterus, Saurichthys (= ? Gyrolepis), ? Cheirolepis. 



Professor J. V. Carus 8 has recently adopted the following classification of the 

 Ganoidei into sub-orders : — 1, Teleosteoidei (including Amia, Leptolepis, Megalurus, 

 Caturus); 2, Hoplopleuridce ; 3, Lepidosteidei ; 4, Lepidopleuridcs; 5, Crossopteryyii ; 

 6, Chondrostei ; 7 , Acanthodida ; 8, Phractosomata (= Placodermi -f- Cephalaspida) . 



The Palceoniscidce find their place among the Lepidosteidei in the following manner : 



1 'Quart. Journ. Geol. Soc.,' August, 1866, p. 315. 



2 Op. cit., German edition, pp. 45 and 47. 



3 'Handbuch der Zoologie,' von J. Victor Carus und C. E. A. Gerstaecker,' Bd. i, 2te Halfte, Leipzig, 



A. Bony Fishes with free gills {Teleostei). 



1. Without air-duct (Acanthopterygii), (P/tysoclysti, s. Acanthopteri) . 



2. With air-duct {Physostomi, s. Malacopteri) . 



1875. 



