20 DEVONIAN FAUNA. 



Size. — Length 2'2 mm. ; height 1*3 mm. 



Locality. — There is one specimen in the Porter Collection from Pilton, 

 associated with a value of Strophalosia productoides. 



Bemarlcs. — This species bears great resemblance in shape, ornament, and 

 markings to Beyrichia clathrata, Jones,^ though differing somewhat in each 

 particular. It appears to stand about halfway ^ between that species and Leperditia 

 mtmdula, Ulrich,^ being nearer to the former in general contour and ornament and 

 to the latter in outline. It is possibly the same as the latter, though it slightly 

 differs from it in the size and shape of the furrow. In any case, however, as it 

 evidently is a Primitia, and has no connection with P. onundula, Jones, we are 

 obhged to retain our proposed name. 



4. (reww-s— Beyrichia, M'Coy, 1846. 

 1. Beyrichia .equilatera, Hall.^ Plate III, fig. 15. 



? I860. Beyeichia. equilateea, Hall. Cauad. Nat. and Geol., vol. v, p. 158, 



fig. 20. 

 ? 1868. — — Dawson. Acad. Geo!., ed. 2, p. 608, fig. 217. 



? 1878. _ _ _ Ibid., p. 609, fig. 217. 



? 1890. — .aiQUiLATEKA, Jones. Quart. Journ. Geol. Soc, vol. xlvi, p. 18, 



pi. ii, fig. 6 ; and p. 552. 

 ? 1891. — — — Canad. Micro-Palaeont., pt. 3, p. 72, 



pi. xi, fig. 6. 



Description. — Valve short, suboblong, convex. Dorsal border long, straight. 

 Ventral border semicircular. Ends equal, gently and evenly curved. Valve with 

 three subequal parallel lobes, separated by two narrow furrows. 



Size. — Length "7 mm. 



Localities. — Several specimens are in my Collection from Saunton Hotel. 



Remarhs. — The specimens are all very much squeezed out of shape; and, 

 probably, the one figured has been shortened from that cause. On the whole, 

 however, they seem to be distinguished by three elongate equal lobes. 



Affinities. — It appears so closely to resemble B. seqiiilatera, Hall, as given 

 by Jones, that I am inclined to think it identical. 



1 1857, Jones, ' Ann. Mag. Nat. Hist.,' ser. 3, vol. i, p. 242, pi. ix, fig. 1. 



2 Dr. Holzapfel translates this phrase, which I used in vol. i, p. 10, in reference to a Trilobite, by 

 the word " Mittelform," and then proceeds at great length to prove me incorrect in so calling it. The 

 simple answer is that I never called it a " Mittelform " at all. In stating that in appearance it stood 

 midway between two other species I in no way implied, or intended to imply, that it was a passage- 

 form between them. 



3 1892, Ulrich, ' Amer. Geol.,' vol. x, p. 265, pi. ix, figs. 4—8. 



