L. M. Lamhe — Fish Fauna of the Albert Shales. 167 



boniferous System in Scotland, and it is the opinion of the 

 writer that the Albert shales should still, as formerly, be 

 regarded as of Lower Carboniferous age. 



The fish fauna of the Albert mines and vicinity has been 

 considered for some years to consist of the following species : — 

 Rhadinichthys alberti (Jackson), R. cairnsi (Jackson), R. 

 modulus Dawson, Elonichthys browni (Jackson) and E. 

 jaoksbni (Dawson), and lately Eastman has described a new 

 form of small size under the name Elonichthys elegantulus 

 (Iowa Geol. Survey, vol. xviii, 1908). 



After a careful study of all available material the writer is 

 forced to the opinion that R. cairnsi is not distinct from R. 

 alberti, that E. jacksoni is the same specifically as E. browni, 

 and that R. modulus is more properly referable to the genus 

 Canobins of Traquair. The generic position of E. elegantulus 

 is considered to be problematical ; the small size of this 

 species in conjunction with its generally imperfect state of 

 preservation leads the writer to suspect that it may be the young 

 of one of the species already known from the Albert mines, 

 possibly of R. alberti. ■ 



This fauna thus appears to consist of the three species 

 Rhadinichthys alberti, Elonichthys browni, and Canobius 

 modulus. To these may be added a fourth regarded as new, 

 belonging to the genus Elonichthys, and for which is proposed 

 the name E. ellsi, in honour of Dr. R. W. Ells, who many years 

 ago obtained the type and only known specimen at the Albert 

 mines. 



The ornamentation of the scales, more especially of the 

 anterior flank scales, in these species is thoroughly distinctive 

 and is one of the most useful characters available for the deter- 

 mination of poorly or partially preserved specimens or even 

 of scattered scales. 



With the following short descriptions of the four above 

 mentioned species are given figures of the anterior flank scales 

 and, in the case of three of them, of the posterior Hank scales 

 also. 



Rhadinichthys alberti (Jackson). 



Palceoniscus alberti Jackson, 1851. Report on the Albert Coal 

 Mine, etc., Boston, p. 22, plate I, fig. 1, plate II, figs. 2, 2 

 bis, 3, 4, 5, 8 and ? 6. 



Palceoniscus cairnsii Jackson, 1851. Ibid., plate I, fig. 3. 



This species is the first of the Albert mine fishes described 

 by Jackson. 



It is of small size, rather slender, fusiform, averaging in 

 length about 8\5 cm . Greatest depth of trunk in advance of 

 the pelvic fins, slightly over one-fifth the total length. Head, 



