MIDDLE BALA GROUP. 

Names and References: Observations, &ce. 


Prosar ae Reference to McCoy’s 
Drawers: Synopsis: and Figures of Genera. 
Gm 
| 
| 
| 
Gm p. 319. 
| 
Gm » do. 
Gm do. 
| 
Gm | 
) | 
an p. 323. 
Gian Pl. 11, fig. 26, p. 323. 

Appendix A. p. VII. 
Trocholites, p. 324. 
Numbers and Localities 

Orthoceras, sp. allied to O. dulce, Barrande. 
The ribs apparently visible on the cast. 
(Ringed or Annulate species— Cycloceras, McCoy.) 
Orthoceras annulatum, Sow. A cosmopolite 
species, at least in N. Hemisphere. 
Orthoceras Ibex, Sow. (Siluria, 2nd ed. pl. 29, 
| figs. 3, 4). 
Orthoceras arcuoliratum, Hall (Pal. N.Y. 1. 
pl. 42, fig. 7). 
Ormoceras, Stokes. Differs from ordinary Or- 
thoceras in having the siphuncle thicker 
and formed of bead-like pieces. 
Ormoceras 

, new sp. 
Lituites cornu-arietis, Sow. (Siluria, 2nd ed. pl. 
7, fig. 10). 
Lituites anguiformis (Trocholites, Hall), The 
Trocholites have usually whorls, wider than 
they are deep; ¢.e. the transverse diameter 
is greater than that from back to front. 
| Lituites (Trocholites) planorbiformis, Conrad 
(Salter, Mem. Geol. Surv. 11. pl. 25, fig. 5). 



a. 176*, Holbeck gill (no- 
dules in slate rock). 
a. 176, Coniston. 
Coniston. 
a. 171, Wrae Quarry, Up- 
per Tweed. 
a. 170, Cymmerig Brook, 
Bala. 
a. 230, Coniston. 
a. 165, Mynydd Fron Frys, 
near Chirk. 
a. 162, Cymmerig Brook 
Bala. 
