90 DEVONIAN FAUNA. 



They are evidently casts of a very thick shell, and show traces of a few 



transverse ridges of growth. In the neighbourhood of the umbo are a few 



prominences, indicating indented pits in the inner surface of the valve. The 



muscle-scars seem rounded and unusually and equally large ; the anterior scar 



is situated halfway from the apex to the centre of the anterior margin, and 

 the posterior scar much nearer to the centre of the posterior side. 



II. Family — ARCTiciDJi;, B. B. Newton, 1891. 

 Cyprinidj;, Gray, 1840. 



1. Genus — Cypricaedinia, Ball, 1859. 



1. Cypeicardinia scALARis, FhUUjjs, sp. Plate IX, figs. 20, 21. 



1841. MoDiOLA scALAEis, Phillij)S. Pal. Foss., p. 137, pi. Ix, fig. 62*. 

 ? 1858. Ctpeicardia impeessa, In Baer and Helmersen's Beitr. Euss. Eeiches, 



Band xxi, p. 106, pi. iv, figs. 4 a, h. 

 1892. CiTEiCAEDiNiA SCALAEIS, WMdhome. Dev. Faun., vol. ii, p. 5, pi. i, 



figs. 6—8. 

 ? 1894. — Sandbeegeei, Holzapfel. Abhandl. k. Preuss. Geol. 



Landes., n. s., pt. 16, p. 181, pi. xvi, fig. 3. 

 1895. — LIMA (Schnur), Beushausen. Ibid., n. s., pt. 17, p. 182, 



pi. xvi, fig. 1. 

 1895. — SCALAEIS, Beushausen. Ibid., p. 179, pi. xvi, fig. 2. 



? 1895. — Sandbeegeei, Beushausen. Ibid., p. 181, pi. xvi, fig. 3. 



Localities. — In the Barnstaple Athengeum are two specimens on a slab from 

 Bradiford and one from Top Orchard ; in the Porter Collection two from Pilton ; 

 and in my Collection six from the lane between Wrafton and Heanton. 



Bemarhs. — After comparing these with specimens from Lummaton I feel no 

 doubt that they belong to Phillips's species. As their surface is often much 

 decayed, their markings are not always so definite, but their character seems the 

 same, and their shape varies within the same limits. They seem still smaller in 

 size. 



I much regret that I am unable to follow Beushausen in separating the three 

 species quoted above from his recent masterly work. Even if the distinctions 

 which the learned German draws are permanent in the Continental specimens, it 

 appears to me that they are unlikely to indicate more than local varieties. As far 

 as I can see, English specimens might be selected which would be ranked in each 

 of them. It would seem that it is not always the same valve which is the largest 

 in the English species, and that the median constriction varies much in its strength. 



