Dr B. H. Traquair on Fossil Fishes from Oil Shales. 117 



faces finely and irregularly striated. In some instances the 

 peculiar styliform bone — described by some authors (Eomer, 

 Grey-Egerton) as the mandible of Acanthodes, by others 

 (Troschel, Kner) as the hyoid — was found lying closely along 

 the inner and lower margin of the dentigerous bone in ques- 

 tion. All doubt as to these jaws with their singular teeth 

 being Acanthodian in their nature was, how^ever, removed 

 by their occurrence in situ in a few fragmentary specimens 

 of fishes of this family, some of which Messrs Hancock and 

 Atthey referred to the Acanthodes Wardi of Sir Philip Grey- 

 Egerton, constituting for it, on account of the peculiar denti- 

 tion, the new genus Acanthodoysis ; others they referred to 

 a new species of the same genus, viz., Acanthodopsis Fgertoni. 



There does not, however, appear to me to be any real 

 evidence of the identity of Acanthodopsis Wardi of Hancock 

 and Atthey with the Acanthodes Wardi of Egerton. I have 

 carefully examined the specimens (now in the Newcastle 

 Museum) which were used by Messrs Hancock and Atthey 

 for their descriptions, and I must own that they seem to me 

 to be too fragmentary to justify any such identification. It 

 is also somewhat remarkable that in the North Staffordshire 

 fish shales, where Acanthodes Wardi is abundant, the jaws of 

 Acanthodojms have not yet, so far as I am aware, been 

 found ; indeed, Mr Ward, whose experience as a collector in 

 that district is so well known, writes to me that he has 

 never yet seen the jaw in question. Although Acantho- 

 dopsis occurs sparingly in the coal measures of Scotland, as 

 at Falkirk and at Smeaton, near Dalkeith, such jaws have 

 also as yet never occurred in the Calciferous Sandstone series, 

 or in the " edge coal " strata of the Carboniferous Limestone 

 group, in which other Acanthodian remains are by no means 

 uncommon. 



The true dentition of the fish named Acanthodes Wardi by 

 Sir Philip Grey-Egerton has not yet been determined, and 

 until that is the case, I think it preferable to retain it in the 

 genus Acanthodes, as distinct from Acanthodojms Wardi of 

 Hancock and Atthey. In similar circumstances, a similar 

 treatment should be accorded to other Acanthodes-like fishes 

 from the carboniferous formation. 



