MIDDLE BALA GROUP. 









cee Reference fo McCoy's Names and References; Observations, &c. Numbers and Localities. 
Drawers. | Synopsis: and Figures of Genera. 
Gk C. brevicapitata, Calymene Senaria, Conrad (Salter, Mon. Brit. | Bryn Melyn, Bala; Cefn 
Pl. 18, fig. 6 (not 4, 5), Trilob. 1865, pl. 9, figs. 5—11, p. 97). One | Coedog; Llanwddyn; Alt- 
some specimens labelled and of the very common Bala or Caradoc fossils | yr-Anker, Meifod ; Conis- 
catalogued as C. subdiade- —appearing to inhabit every kind of sea- | ton; Horton (very large). 
mata. bottom. It is often confounded with the | a. 135, Pwllheli; High 
C. Blumenbachii, var. brevicapitata, Port- | Haume. 
lock. a. 136, Applethwaite Com- 
mon. 
Gk Calymene Blumenbachii, Brongniart (Sil. Syst. 
pl. 7, figs. 6, 7. Salter, Mon. Brit. Trilob. 
p. 93, pl. 8, figs. 7—16). The common Dud- 
ley trilobite, in its typical form, with a large 
broad glabella, is not found in the Bala rocks, 
but a variety, with narrower glabella, viz.— 
Gk C. brevicapitata, p. 165. Calymene, var. Caractaci, Salter (Mon. Brit. | a. 136*, Horderley; above 
Tril. p. 96, pl. 9, figs. 3—5. C. brevicapitata, | Rother Bridge. 
Portlock, Geol. Rep. on Tyrone, &c.), is one 
of the frequent fossils in the Bala beds. 
Gk Pl. 1 G, figs. 24—31, Homalonotus bisulcatus, Salter (Mon. Brit. | b.154, Maes Meillion, Bala; 
p- 168. Tril. 1865, pl. 10, figs. 3—10). Homalonotus, | Bryn Eithin, Penmachno ; 
so named from the uniform scarcely lobed | Garefawr, Welchpool ; 
condition of the dorsal surface, is very like | a. 111, Pwllheli; Acton 
Calymene else, and always accompanies it Scott, Shropshire (where 
in the old rocks. It however ascends in | tt.is large and abundant). 
force into the Devonian, while Calymene 
does not. 
Gk Homalonotus Sedgwickii, Salter (Mon. Brit. | a. 228, Llanwddyn, Mont- 
Tril. p. 107, woodcut, fig. 25). gomeryshire; a, 227, Ra- 
venstonedale. 
Gk Pl. 1 £, fig. 20, p. 168. Homalonotus rudis, Salter (Mon. Brit. Tril. | a. 229, Capel Garmon. 
pl. 10, figs. 12—14). 
Gk Tsotelus, p. 169. Asaphus Powisii, Murchison (Salter, Mon. Brit. | a. 190, Pen Cerrig Serth, 
Tril. pl. 23, figs. 2—5, p. 154). As charac- | N. of Bala; Bryn Eithin, 

teristic of the Middle Bala rocks as the 
A. tyrannus of the Lower Bala, easily dis- 
tinguished by the faint ribs of the tail. 
Penmachno; Bwlch-y-groes; 
Meifod ; Llanwddyn. 
