278 
SILUBJA. 
[Chap. XI. 
(Hexacrinus, Platycrinus, &c.) ; with the Trilobites Bronteus flabellifer, Goldf., 
Elarpes macrocephalus, Goldf., Phacops, &c. The same species are found in the 
Middle Devonian limestones of Combe Martin and Ilfracombe in North Devon, 
with also many other equally important Shells characteristic of this stage, viz. 
Rensselseria stringiceps, Boemer, Meristella plebeia, Sow., Streptorhynchus 
umbraciiliim, &c, associated with the usual and characteristic Corals Helio- 
phyllum Hallii, M.-Edw., Cyathophyllum csespitosum, Goldf., C. Boloniense, 
Blainv., Cystiphyllum vesiculosum, Goldf., Hallia Pengellyi, M.-Edw., and 
Pleurodictyum problematicum, Goldf. 
Fossils (74). Fossils of the Middle Devonian Limestones. 
1. Calceola* sandalina, Linn. 2. Megalodon cucullatus, Sow. 3. Murchisonia bi- 
lineata, G-oldf. 4. Stringocephalus Burtini, Def. 5. Atrypa desquamata, Sow. 
The curious fossil called Sphasronites tessellatus by Sir H. De la Beche also 
occurs here. It is not, however, a Cystidean, that family being confined to the 
Silurian rocks, but is, perhaps, a complex sponge, as is also Steganodictyum of 
M'Coy, from the slates of Polperro, Cornwall. The fossils of the calcareous 
slates, indeed, which range throughout the southern parts of Devon and Corn- 
wall, are for the most part the same as those of the limestones — Atrypa desqua- 
mata and Phacops laciniatus being the commonest forms at Padstow, Liskeard, 
and St. Keyne. 
To return to the section, p. 272. The highest rock which is there 
classed as Devonian (f), and which lithologically is an upward con- 
tinuation of the slaty series, differs very considerably on the two sides of 
the trough — so much so that there is much difficulty in identifying the 
beds on the southern side of the trough with those on the northern. 
On the southern side the strata, by their schistose and calcareous nature, 
as Veil as fossils, truly represent the Upper Devonian limestones and 
schists of Germany, of which mention will be made in a subsequent 
Chapter ; but the beds of the Barnstaple section differ much in lithological 
character and fossil contents, and indicate, both in my opinion and in that 
* This was formerly regarded as a Brachiopo- a Zoophyte belonging to the Actinozoa Kugosa : 
dous Shell ; but Lindstrtfm has shown that it is Geol. Mag. vol. iii. pp. 356, 406. 
