110 OLD RED SANDSTONE FISHES. 



finest examples of Asterolepid remains yet discovered, and clearly show all the 

 salient features of Bothriolepis in a manner never before exhibited. Unfortunately, 

 Mr. Whiteaves does not seem to have then had complete access to the literature of 

 the subject; for, apparently unaware of what Lahusen and Trautschold had 

 written, he said : " It is still open to question, however, whether the genus Bothrio- 

 lepis is or is not a valid one and sufficiently distinct from Pterichthys." 



In my essay on the structure and classification of the Asterolepidae published 

 in 1888, I considered that I had brought together the main facts regarding this 

 genus, which facts conclusively showed that although Bothriolepis was indeed a 

 veritable Asterolepid, nothing could be more salient than the generic distinctions 

 which separate it from both Pterichthys and Asterolepis ; and I also showed that, 

 besides the " Pterichthys " major of Agassiz, two other reputed species of 

 Pterichthys, namely, hydrophilus, Ag., and macrocephalus, Egerton, must also be 

 transferred to Bothriolepis. On the appearance, a year later, of the late Professor 

 Newberry's ' Palaeozoic Fishes of North America,' I was, therefore, rather 

 surprised to find that in treating of Bothriolepis he seemed to consider its relations 

 to Pterichthys as still a matter of uncertainty ! His remarks certainly do not 

 indicate that he had given much study to the subject. 



On the other hand, we find that the treatment accorded to Bothriolepis in the 

 second part of Dr. Smith Woodward's 'Catalogue' published in 1891 is wholly 

 accurate and up to date. In the following year the same author published a noteworthy 

 contribution to our knowledge of the genus by accurately figuring the " maxillary " 

 plates, the form of which had been somewhat imperfectly given by Whiteaves. 



As Agassiz had, years previously, failed to diagnose fragments of the arm of 

 Bothriolepis, and had attributed them to a new genus, namely, " Placothorax" 

 so in 1856 we find Leidy figuring the distal part of a Bothriolepis limb as a spine, 

 to which he gave the name of Stenacanthus nitidus. 1 And thirty-five years later a 

 similar mistake was made by Cope, 2 who interpreted a corresponding fragment of 

 Bothriolepis as a spine of Holoiiema. This has been already noted by Dr. Smith 

 Woodward. 3 



Restoration of Bothriolepis. — British specimens of the genus are mostly frag- 

 mentary; if entire, as in the case of B. hydrophilus of Dura Den, then they are 

 not well preserved. To gain a proper insight into our native species it will, there- 

 fore, be as well in the first place to illustrate, by a couple of restored figures, the 

 structure and configuration of a non-British species, B. Canadensis, of which the 



1 J. Leidy, " Description of some Remains of Fishes from the Carboniferous Formations of the 

 United States," ' Journ. Acad. Nat. Sc. Philadelphia,' vol. iii, second series, pt. iii, 1856, p. 164, 

 pi. xvi, figs. 7 and 8. 



2 " On the Characters of some Palaeozoic Fishes," ' Proc. Nat. Mus.,' vol. xiv, 1891, p. 456. 

 :i ' Geol. Mag.,' vol. ix, 1892, p. 234. 



