^4 CANADIAN MICRO-PAL.EONTOLOGY. 



definitely correspond to the same features in our pi. xi, tig. 1; so, also, 

 the isolated and oval middle lobe, and the long, strong, curved posterior 

 lobe of the same tigure. 



It will, I think, be most convenient to accept the published descrip- 

 tion (1860) as belonging to B. (vquilatera, Hall, and to regard the little 

 woodcut on the same page as belonging to the other species occurring 

 80 abundantly with B. wquilatera. 



3. Beyrichia tuberculata (Kloeden). 

 PI. 11, fig. 3. 



Battm tuber culatus, Kloeden (pars). Versteinerungen der Murk Brandenburg, 



1834, p. 115-117, pi. i, figs. 21-23. 

 Beyrichia Uiberculata, Boll. Pahvontognipliica, vol. T, 1847, p. 127; Archiv des 



Vereins der Frounde der Naturgeschiclito in Moklen- 



burg ; 16 Jahr., 18b2, p. 119, pi. i, figs. 1 a, 1 b. 

 Agnofitus t iberculatiis, Quenstedt. Petrefactenkunde, 1852, p. 302, pi. xxiii, figs. 



25-28. 

 Beyrichia tuberculata, Bronn and Roemor. Letluea geognostica, 1854, vol. I, p. 



536, pi. x^ figs. 9 a-d. 

 Beyrichia tuberculata, Jones. Ann. INIag. Nat. IIist.,ser. 2, vol. XVI, 1855, p. S(), 



pi. V, figs. 4-9 b ; Trocoed. Geol. Assoc, Pal. J>iv. Entom., 



1869, p. 12, figs. 12 a, b, c; Geol. Mag. Dec. 2, vol. Ill, 



1881, p. 344, pi. X, figs. 8-10; Ann. Mag. Nat. Hist., ser. 



6, vol. I, 1888, p. 402, pi. xxi, fig. 12. 

 Beyrichia tuberculata, Roemer. Letha'a pahco/oica, 1876, pi. xix, figs. 9 a-d. 

 Beyrichia tuberculata, Krause. Zeitschr., d. Deutsch. geol. Gesell., vol. XXIX, 



1877, p. 30, pi. i, figs. 12 a, b. 

 Beyrichia tuberculata, Ploernes. Palseontologie, 1884, p. 379, figs. 525 c. d. 

 Beyrichia tubercufata, Renter. Zeitschr. d. D. g. Ges., vol. XXXVII, 1885, p. 632, 



pi. XXV, figs. 1 A, 1 B. 

 Beyrichia tuberculata, Zittel. Handb. Palseontol., vol. II, 1885, p- 553, figs. 739,740. 

 Beyrichia tuberculata, Verworn. Zeitschr. d. D. g. Ges., 1887, p. 31, pi. iii, fig. 12. 



Eeferring to the memoirs by Krause and Router, above noticed, the 

 student will find the names of several other authors who have referred 

 to this species, from either a geological or a paleontological point of 

 view. 



Several varieties o^ this species are noticed, and in many cases figured 

 and named in some of the memoirs above enumerated. 



It may be remarked hei'c that the tubercles present on the surfiice of 

 the lobes and margins of perfect valves are missing on casts of the 

 insides, as is well shown among the figures on pi. x of the '*Gcol. 

 Mag.," 1881. 



