OLD KKD4AND8TONK. 



OI.IIA. 



I of UM series do not however always consist of 



.frequraUy composed of beds of sandstone, 



and tMly grained, and alternating with a few imperfectly- 

 til d mottled marb. The lower portion capping the escarpment 

 rf UM Contoa* ia Herefordshire furnbhe* thick beds of valuable 

 fr^ffrlinj material. *iH b oonaaionally quarried for tile*. The upper 

 b*d* an far UM most part lees compact, and commencing a* a fine 

 eomaHonwraU thry afterward become coarser, and alternate with bands 

 of red aid green argUlaowu* mart Fine examples of the conglomerate 

 bad* (attaining near Abergavenny a thickness of 200 feet) may be een 

 on UM bank* of UM Wye between Boas and Monmouth, and again on 

 Ih* right bank of that beautiful river to the north of Tintern Abbey. 



The Cometon* nnijalsln of a number of argillaceous marly beds 

 sometime* alternating with sandstone and sometime* with impure 

 MrortTTiT. affording by doaomposition the soil of the richest tract* of 

 Herafordahin aod Monmouthshire. The lower part of this rock very 

 often contains flaggy bad*, some of which an extensively quarried 

 Dear Downton Hall, the stone being of a greenish colour and highly 

 and usually more or leas intermixed with party-coloured 

 i or soft argillaceous sandstones, not so compact as the rock which 



as* them. The surface of the sandstone b frequently worn into 



irregular holes and patches. 



Bat the subdivisions of the sandatone* are too entirely local to allow 

 of any lithological character being given which can apply to more than 

 a very limited" district. Generally speaking, the impure concretionary 

 limsatrni which b more especially denominated Cornstone, appear* 

 a* intervals in irregular lenticular rnsssia throughout the district, con- 

 tnctinc and expanding in the most capricious manner; sometime* 



1 expanding 



by finer and more crystalline limestone, and sometimes 

 ajeanaallnf. with hard flaggy sandstones. Nearly the whole of the 

 central and northern parts of Herefordshire, and the contiguous part* 

 of Shropshire and Worcestershire, an occupied by this formation ; 

 and iu vast ihlrknsas b well displayed in the hills crossed by the new 

 road from Leominster to Hereford. In the northern portion of the 

 range, and near the mouth of the Towey in Caenuarthenihire, the 

 Hmaetone* an most fully developed, becoming much thicker and also 

 more crystalline than in other parts. 



In Scotland the uppermost bed* are highly arenaceous, and often 

 cooabt of ssmUVniT conglomerate*. The intermediate calcareous band 

 b barren of fossil*, and i* of somewhat singular composition, yielding 

 unequally to the weather, and exhibiting a breoebted aspect It 

 Mrt4- massrs of chert exceedingly bard, and these, from the manner 

 in which they an incorporated with the rock, appear to have been of 

 contemporaneous origin. The bed b several yards in thickness, and 

 b very persistent, bring found both in Moray and in Fife, localities 



The middle group of UM Old Bed-Sandstone of Scotland, correspond- 

 ing to the ComatoM of Kngland, b developed in Forfarshire, in 

 Morayahire, and in the Gray-Sandstone of Balruddery, where the lower 

 bed* an absiat. It b represented a* consisting, for the most part, 

 of rook* of a bluish gray colour, sometime*, as at Balniddery, resem- 

 bling the Silurian mudstones, at other* forming a hard fiaule flagstone 

 exported aa a paving-stone, and occasionally appearing in beds of 

 friabb stratified day. easily washed away by the sea. The colour 

 throughout is gray, and in this repect differs essentially from 

 bods, which are chiefly red and green 



The baa* of UM whole system b represented by Mr. Miller a* con- 

 sifting of an extensive and thick conglomerate rising into a lofty 

 nounlain chain in the county of Caithness, and attaining an elevation 

 of WOO feet in the bill called Morrbeim, but a great thicknos* of 

 aieaansnas strata, containing conglomerate* of various magnitude, 

 IrtHiau** beta sea thaa* and UM middle bed*. 



The Devonian Bad* p remit a aerie* so distinct that no relation* of 

 I condition eta ha traced between them and the 



OM R*d4Jad*tooea. The upper bed* on which the culms of Devon- 

 hire repose, eonabt of ooars* red Baa and slates, sometimes alternat- 

 b with or overlaid by other slates and limartonee, while the lower 

 bad*antobeeoo*^tfaraoetjUMCaleareott**late*of Cornwall and 

 earth Devon. The calcareous alatea an occasionally foastliferous, 

 aod an bated upon aa impure limestone. The Plymouth Limestone 

 b> UM south, aod a group of eoarat anoaeaous bed* in the north of 

 Dram together with the general atria* of Cornish rock*, are all 

 kaoradcd asBoaa; than calcareous alatea. Throughout the whole aerie* 

 fasafb oeaar. but the* are very unequally distributed, being locally 

 abvstaant, although owing to UM matamorphic character of many of 

 *" bad* they an inmitimai much altered, and frequently obliterated. 



b largely developed in Ireland, and U 

 tmg all those parts of UM series which 



Tb* 



Thta fsmatlaa. ta wll repreaantod in Belgium by a eerie, of bed* 

 aawMamf of 1SOO (rat of strata. They an principally composed of 

 a yeUuirba mssdaloa* ahoraattng wUh ahal* and aaloanou* bed*. 



The Davoaba or Old Had-Saodstooe* of Ru*ab occupy a tract 

 Mat ly a* brff* aa UM whole of the Rritbh Islands. They rest con- 

 formably upon low plateaux of ailurian rock., and attain a height of 

 from MO to MM f**t above UM **a level 



This formation is repeated with nearly the same mineral characters 

 and organic remain* in America. It i* found iu both North and South 

 America, 



The following an the genera of the Invertebrate Fossiln found in the 

 Devonian Group, a* given by Mr. Tennant in hi* ' Stratigraphioal 

 T :_ ~r n_:*:_i. * ?*_> . 



List of Britiah Fossils' : 

 Jfomm criirwum, Goldf. 



A mpltfui tortwtitt, Phil. 

 Aitrra, Blainv., S specie*. 

 Aulopora amglamerata, Goldf. 

 CbaMopom raaiosa, PhiL 

 Cosn'nopora placenta, Goldf. 

 OyaOiopkfUiM, 2 species. 

 CyttipkyUum, 2 specie*. 

 Patatita, 4 specie*. 

 PamltUa, 5 *pecia*. 

 Qlawxnwme kipinnaia, PhiL 



Amorphotoa. 



Scyphia turbina'a, Goldf. 

 Zoopkyta. 



li'tryonin ripitttria, Goldf. 

 Jfemitrypa ocultUa, Phil. 

 MiUepora gracilii, Phil. 

 Millepon liniiit, PhiL 

 Petrain, 4 species. 

 Portia pynformu, Ehrenb. 

 Rtroinatnpora, 2 specie*. 

 Slramh'iJa, 2 specie*. 

 fi/rinyupora catenate, Mart. 



E'Mnodermata. 



Platycrintu, 2 species. 

 Taxotrinm maerodactylui, Phil. 



AddocruHu kyttrix, Phil. 

 Cyatkocrinia, 8 species. 

 Pentatrtmatitet ovaJ.it, Goldf. 



Criufacca. 



Bronte* JlabMifrr, Ooldf. Olenni punctattu, Stein. 



Calymene Sternbcrgii, Munat Pkacopi, 3 species. 

 Jfarpet macroctpkaltu, Goldf. 



Conchifera Dimyaria. 



Corbula Hrnnahii, Sow. Mytilut Damnoniensit, Phil. 



CitcMaa, 7 ipecies. Nucula, 3 specie*. 



Cypricardia, 2 species. PUurorltynciu, 2 species. 



MnjaJodon, 2 species. Puilattra, 3 species. 



Modiola, 3 species. Sanguinolaria, 3 species. 



Aticula, 9 specie*. 

 Pteten, 8 specie*. 



Conckifcra Monomyaria. 



Potidonomya, 2 specie 

 'Pterinea, 3 specie*. 



Atrypa, 19 species. 

 Calceola taxdaJini, Lam. 

 ChotuUt, 3 ipecie*. 

 Leptana, 7 specie*. 

 Orl hit, 16 species. 



Acrorulia ligmoitlalit, Pbil. 

 Ruccinum, 4 specie*. 

 Kuomphaliu, 3 specie*. 

 Loxoiuma, 8 species. 

 Macrockeilui, 3 species. 

 il KrcAiatmto, 6 specie*. 

 liwtx karftUa, Sow. 



BratHiopoda. 



Product*!, 6 species. 

 Spirifer, 33 species. 

 Strigocrplialiu, 3 species. 

 Ttrcbratula, 31 species. 



Gnttcropoda. 



.\~atica, 2 species. 

 Nerita, 2 specie*. 

 Platycerai vetuilum, Sow. 

 Plsurotomaria, 8 species. 

 SMvutoma, 2 species. 

 Trotkut Boueii. Stein. 

 Turbo, 3 species. 



BcUeropkon, 8 species. 



JJeltropoda, 



Porceilia Wuodwardii, Sow. 

 PUropoda. 

 Crtteu dimiJiatuiii (Orlhocerat, *p. Sow.). 



(.'lymenia, 7 species. 

 Cyrtoctrai, 12 specie*, 

 Omialitei, 11 species. 



Ctpkalopoda. 



tfautiliu, 2 specie*. 

 Ortkoccrai, 12 species. 



OLEA, a genu* of Plant*, the type of the natural order OUacca. 

 It lias a 4 -cleft corolla, a berry with two brittle 1 -deeded cells, one of 

 them generally abortive. The leave* undivided. Flowers greenish, 

 clustered, axillary. 



0. Europaa has lanceolate quite entire 2 coloured leaves, with 

 axillary racemes. It grows wild in rocky places in Italy. It differ* 

 from most trees, except th Sweet Bay (L<tni-* nobUit), some species 

 of Cor*xt, and a very few others, in yielding n fixed oil from the 

 pericarp ; the seed being the source of fixed oils iu most plants. The 

 oil which U expressed from the ripe fruit immediately after being 

 collected ia most esteemed, and called Virgin Oil, Oleum Provinciate. 

 That which is moat highly priced come* from Nice and Genoa. When 

 the oil is extracted by a stronger pressure, or by the aid of heat, or 

 after the olive*, having been collected into heaps, have remained till 

 a kind of fcmicntition lias occurred, it is the common Olive Oil, tin' 

 properties of which vary in proportion as the fermentation has been 

 of long or short duration. An oil of still inferior quality U obtained, 

 when the husk of the olive, after the former treatment, is boiled iu 

 water. Thin kind in employed solely for the preparation of soap. 



Virgin Oil it of a very pale-yellow or yellowih-green colour, more 

 limpid when fine than any other fixed oil; inodorous; when fresh, 

 but emitting a very peculiar odour when old ; taste purely oily but 



