08 
SILUKIA. 
[Chap. IV. 
Soudley and Enchmarsh beds of freestone were shown to range to the 
Long Lane and other quarries of sandstones with calcareous courses. 
The upper beds, which at Cheney Longville pass up into sandy shale, 
were described as very fine-grained, slightly micaceous sandstone, of 
green and dingy olive-green colours, in beds one to six inches thick, and 
as enclosing here and there shelly calcareous courses, or impure lime- 
stones. Looking to the composition of these beds, and others lower in 
the series and nearer to the eruptive ridge, I inferred that some of them 
must have been deposited in a sea rendered turbid by volcanic action, so 
as to form strata which, if fossils were excluded, mineralogists would 
refer to the ' sandy clay-stone ' of Jamieson. I then also stated that they 
constituted the last lithological term in that series of volcanic rocks of which 
a description will be given at the end of this Chapter. 
The remains of fossils often so abound as to render some of the courses 
limestones ; these have occasionally been burnt for use, and are known 
to the workmen of the neighbourhood as " Jacob's Stones." "When the 
calcareous matter is diffused in small particles through the mass, the 
rock becomes a hard calcareous grit, usually of a whitish drab colour, 
breaking under the hammer with a conchoidal and lustrous fracture. On 
the banks of the Onny, between Horderley and Wistanstow, there is also a 
band of impure limestone, formed, however, chiefly of quartzose pebbles 
cemented by lime. 
Some of the most characteristic fossils of the formation are given in this 
woodcut. 
Caradoc Fossils (13). 
1. Calymene Blumenbachii. 2. Homa- 
lonotus bisulcatus, Salter. 3. Phacops 
truncato-caudatus, Portl. 4. Tentaculites 
anglicus, Salter. [5. Lingula crumena, 
Phill.*] 6. Orthis testudinaria, Dalm. 
7. O. vespertilio. 8. Strophomena te- 
nuistriata. 9. S. grandis. 10. Bellero- 
phon bilobatus. 11. B. nodosus, Salter. 
12. Orthonota nasuta, Conrad. 13. Ne- 
bulipora lens, M'Coy. 14. Diplograpsus 
pristis, Hisinger. 15. Graptolithus prio- 
don. 
In addition to the above, the following characteristic fossils are figured in Plates V. 
to VII. or in the woodcuts of the next chapter: — Orthis elegantula; O. flabe:lulum; 
O. Actonise; O. ealligramma; Strophomena expansa ; S. spiriferoides, M'Coy; Leptasna 
sericea ; Modiolopsis orbicularis ; M. modiolaris, Conrad ; M. obliqua ; Bellerophon 
acutus ; Phacops conophthalmus, Eichw. 
(The species with no author's name attached were published in the ' Silurian System.') 
The cuttings along the Hereford and Shrewsbury railroad laid open 
* The Lingula crumena, f. 5, has been placed in the above woodcut by mistake; it belongs to the 
overlying Llandovery rocks, into which the Caradoc passes upwards in South Wales. 
