



5A UPPER CAMBRIAN. 
aaa Reference to McCoy's Names and References; Observations, &e, Numbers and Localities. 
Drawers.| Synopsis: and Figures of Genera. 
Gk A. laticostatus, Asaphus radiatus, Salter (Mon. Brit. Tril. pl.18, | b, 187, Rhiwlas Bala. 
Pl. 1 &, fig. 18 (not fig. 18 a), figs. 1—5). Not quite a common fossil in | [The Girvan locality is of 
which is Lower Bala, p. 170. certain parts of the Bala beds—but yet not | May Hill Sandstone. ] 
rare. It seems only to have lived in cal- 
careous mud. 
Gk Dysplanus centrotus? 178. | Ilenus Bowmanni, Salter (Mon. Brit. Tril. | a. 129, Llanwddyn; 
Teak, Th am, es UB). 1867, pl. 28, figs. 6B—13). A very common | Keisley,near Dufton, West- 
Til. latus, p. 172. fossil. Unlike most of the Jileni it has | morland. 
PINE, fig. 17 only 9 body rings like I. centrotus, Dalm, | b.188, Wrae Quarry, Tweed 
It has been often confounded with that | (J. latus). 
spine-headed species. 
Gk Pl. 1 G, fig. 36, p. 171. Illenus Davisii, Salter (Mon. Brit. Tril. p.194, | a. 130, Rhiwlas, Bala; Glyn 
pl. 29, figs. 10—16). 10 rings to the body, | Diffwys; Llanwddyn. 
very small eyes. 
Gk Pl. 1 G, figs. 833—35, p. 172. | Tllenus Rosenbergii, Eichwald (Salter, Mon. | a. 141, Coniston; Sunny 
Brit. Tril. pl. 29, figs. 2—6, 1867). See dis- | Brow; Horton in Ribbles- 
cussion in Appendix to Synopsis, p. 4, as | dale. 
I. Murchison. 
Gk Illenus, small sp. like Z. Barriensis (probably 

Pl. 11, fig. 3, p. 336, note. 

of the section Bumastus), Mon. Brit. Trilob. 
1867, p. 215, fig. 57. 
Harpes parvulus, McCoy, Synopsis, p. 336, 
note. 
Mollusca Brachiopoda. 
The Brachiopods, few in the existing ocean 
fauna, were of all shells the most prolific in 
numbers and kinds in the seas of the Cam- 
brian and Silurian eras. Some of the 
earliest formed genera—Discina, Lingula 
or their allies—have been already quoted 
from Lower or Middle Cambrian rocks. But 
the great abundance of Orthides, Leptenc, 
and such like shelly forms in the Bala 
rocks give quite a character to the deposit. 

b. 189, Mynydd Fron Frys, 
Chirk. 
b. 228, Wrae Quarry, Up- 
per Tweed. 
