﻿14 GANOID FISHES OF THE CARBONIFEROUS FORMATION. 



Agassiz Pyyopterus Greenochii} but for which I have since established a new genus, 

 Nematoptychius? In this paper the bones of the exterior of the head were described, as 

 well as the conformation of the shoulder-girdle with its interclavicular plates, but I was 

 not then acquainted with the suspensorial and palato-quadrate apparatus, and many other 

 matters of detail which have since come to light. The structure of Nematoptychius was 

 found to agree in all its leading points with that of other fishes from the Edinburgh 

 district classed by Agassiz with Amblypterus and Palaoniscus. 



As regards the curious genus Cheirolepis, many of its head bones were correctly 

 described and figured by Pander in I860, 3 and he proposed to institute for it a distinct 

 family of " Cheirolepidini," although he was also struck by the resemblance which 

 certain of its facial bones bore to those figured by Quenstedt in Palaoniscus. In this 

 view Professor Huxley acquiesced, 4 and, in alluding to the probability of the " Cheiro- 

 lepidini" being referable to the great suborder of Lepidosteidse, he pointed to the 

 branchiostegal rays of Cheirolepis discovered by Agassiz, and to the absence of jugular 

 plates. Powrie, however, in 1867 5 published a paper describing certain plates in this 

 genus, which he considered to be principal jugulars, and referring the " branchiostegal 

 rays " of Agassiz to the category of lateral jugulars, as in Holoptychius, Meyalichthys, &c. 

 But in IS75 6 1 pointed out that those so-called jugulars in Cheirolepis were, in fact, infra- 

 clavicular plates, closely resembling those I had already described in Nematoptychius, 

 &c, and maintaining that the correspondence in general organisation between Cheirolepis 

 and Palaoniscus was so close that they must be included in the same family. I was not, 

 however, then acquainted with a paper by Dr. Karl Martin which had been published 

 two years previously, 7 and in which the same opinion as to the position of Cheirolepis was 

 expressed, though with an appended query. Dr. Martin's paper deals principally with 

 the cranial structure of Palaoniscus and a few other allied genera occurring commonly in 

 the Permian strata of Germany, finishing with general views as to the " systematik " of 

 the group, which will be noticed further on, the original impulse to his researches having 

 been given by the erroneous restoration of Palaoniscus given by Liitken a few years 

 before. 8 Unfortunately Dr. Martin's definition of the family and his account of the 



1 "Description of Pyyopterus Greenockii, with notes on the Structural Relations of the Genera 

 Pyyopterus, Amblypterus, and Eurynotus," 'Trans. Royal Soc. Edinb.,' vol. xxiv, 1867, pp. 701 — 713, 

 pi. xiv. 



2 'Annals and Mag. Nat. Hist.' (4), xv, p. 258 (1875). 



3 " Ueber die Saurodipterinen, Dendrodonten, Glyptolepiden, und Cheirolepiden des devonischen 

 Systems," St. Petersburg, 1860, pp. 69—73. 



4 ' Dec. Geol. Survey,' x (1861), pp. 38—40. 



5 ' Geol. Magazine,' iv, 1867, pp. 147—152. 



6 "On the Structure and Systematic Position of the genus Cheirolepis," 'Annals and Mag. Nat. 

 Hist.' (4), xv (1875), pp. 237—249. 



7 " Ein Beitrag zur Kenntniss fossiler Euganoiden," 'Zeitschrift der deutschen geologischen 

 Gesellschaft,' xxv (1873), p. 699, tab. xxii. 



8 Op. cit., woodcut, fig. 3. 



