Silurian, Rocks of the South of Trelund to those of North Devon. 145 
Brief Description of the North Devon Formations and their Fossils. 
[ Descending order. | 
The fossils marked with an asterisk (*) occur in the Lower Carboniferous and Coomhola beds of the 
S. of Ireland, and have been identified by Mr. Baily, r.¢.s. (Acting Palsontologist to the Survey.) 
(a.) Carboniferous Iimestone (Benn quarry).—Dark, thin-bedded earthy lime- 
stones and shales, dipping S. at 50°-60°.  Fossils—Posidonomya Becher. 
(2.) Carboniferous Slate.—Dark schists (contorted) resting on light-grey slates, 
with calcareous nodules (Barnstaple slates). Fossils—Cyathocrinus distans, Spirifer 
lamimosus, S. cuspidatus, Streptorhynchus crenistria, Chonetes Hardrensis, Belle- 
rophon decussatus, Productus costatus, and Phillipsia seminifera. 
(c.) Pilton Beds.t—Beds of grey, blue and purplish slate and grit, with thin cal- 
careous bands. Principal fossils.—Chonetes Hardrensis,* Productus prelongus, 
P. scabricuius,* Spirifera Urii, Rhynchonella pleurodon,* Orthis interlineata, Stro- 
phomena rhomboidalis * (analoga), Spirifera disjuncta,* Streptorhynchus crenistria, 
Cucullea amygdalina,* Sanguinolites complanatus, Huomphalus serpens,t Ortho- 
ceras cinctum,* Actinocrinus tenuistriatus, Cyathocrinus variabilis, Poteriocrinus 
Susiformis, Phacops latifrons, Calamites and Sigillaria. 
(d.) Marwood Beds or “ Cucullea Beds.”—Hard grey and greenish grits and 
slates, with calcareous bands containing fossils, principally as casts; the beds are 
contorted and thrown into an anticlinal fold N. of Braunton Church. Fossils— 
Lingula squamiformis,* Avicula Damnoniensis,* Cucullea amygdalina,* C. angusta, 
C’. depressa,” C. Harding,” C. trapezium,” Cypricardia deltoidea, Sanguinolites 
mimus, Natica sp. Pleurotomaria expansa, P. gracilis, Orthoceras imbricaium. 
O. tentaculare, Paleopteris Hibernicus (Sloly quarry) Knorria, Sphenopteris, &c. 
(¢.) Pickwell Down Sandstone.—Immediately lying underneath the “ Baggy 
Point ” and “ Marwood Beds,” with Cucullea trapezium, &c., are a series of yellowish 
and greenish flagstones and shales, seen near the village of Upeot, which from their 
position underneath the “Cuculleea zone” and similarity of appearance, I consider 
to be the representatives of the “ Kiltorcan beds” of the south of Ireland with 
Anodonta Jukes and Paleopteris Hibernicus. The Devon beds have not as yet 
yielded fossils; not being, in fact, very well laid open for such a purpose. To 
these beds succeed the “ Pickwell Down Sandstone,” consisting of red and purple 
sandstones, with occasional shaly bands in the upper part, and of greyish hard 
grits in the lower. These beds are well laid open in the railway section south of 
Ilfracombe, and they rise into dry, elevated downs, from whence their name is 
t It will be observed that this fauna is essentially of a Carboniferous type, and is taken from the list 
given by Mr. T. M. Hall. (Quart. Journ. Geol. Soc., Vol. XXIIL., p. 378.) 
Out of 78 genera with 153 species, stated by Mr. Hall to have been found in the “ Pilton” and under- 
lying ‘ Cucullzea beds,” about 42 species are known to occur in the Carboniferous Slate and Coomhola 
Grits of the south of Ireland, and 20 species occur in the “ Ilfracombe beds ” (Middle Devonian). 
oy 0. cenctum occurs, as far as kno W , only In the Carboniferous Limestone. 
