66 CANADIAN MICRO-PALEONTOLOGY. 



8. Beyrichia quadrifida (sp. nov.). 

 PL 11, figs. 9 a and b. 

 Beyrichia, sp. nov. Quart. Jour. Geol. Soc, vol. XLVI, 1890, p. 553. 



Length 1-3 (hinge-line 1*3), height '8, thickness '5 mm. 



Semicircular on the ventral and straight on the dorsal margin ; four- 

 lobed, lobes narrow ; the two behind are nearly equal in length, parallel, 

 slightly curved upwards, joined below, and passing into the base of the 

 front lobe, which, with the divided mid-lobe, is variable. 



Though at first sight very difi'erent from Beyrlch'a claoigera (figs. 7 

 and 8), yet this form presents a passage from it to the four-ridged 

 Beyrichice (plurijugat®), to which Mi*. E. O. Ulrich proposes to apply a 

 distinct specific term. The definite, equal, parallel, narrow lobe in fig. 

 9 is a development of the subsidiary swelling behind the gigot-lobe in 

 figs. 7 and 8, and, as in these latter, the midlobe forms two small, un- 

 equal and oblique lobes or tubercles, within the somewhat Bollia-VikQ 

 curve of the two chief lobes. 



Rather frequent in a dark grey, hard limestone, (Trenton), with 

 Ostracoda, enci-inital remains, and brachiopod shells at Lorette Falls, 

 River St. Charles, Province of Quebec. Collected by Mr. H. M. Ami 

 in 1888. 



9. IsocHiLiNA Ottawa, Jones. 



Leperditia {IsochiUna) Ottawa, Jones. Ann. Mag. Nat. Hist., ser. 3, vol. 1, 1858, 



p. 248, pi. X, fig. 1. 



Jones. Geol. Surv. Canada, Org. Rem., Decade 



III, 1858. p. 97, pi. xi, fig. 14. 

 IsochiUna Ottawa, Jones. Ann. Mag. Nat. Hist., ser. 5, vol. XIV, 1884, p. 345. 



YaR. INTERMEDIA (nOv). 



PI. 10, figs. 10 a, b, and 11 a, b. 



IsochiUna Ottawa, Jones, var. Quart. Jour. Geol. Soc, vol- XLVI, 1890, p. 553. 



Mm. Mm. Mm. 



Fig. 10-Height 4i (Hinge-line.. 3) Height.. 2H Var. .tomec^ia. 



Fig. 11 4J ( 3i) .. 3 / 



Fig. 1 (1858)— Height... 4 ( 3) .. 2 Type. 



Numerous individuals, in limestone belonging to the Chazy Forma- 



