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Bed of Tavy (pebble Beerferrers railway bridge foundations).-

Warm-brown: an uneven-textured granite, some parts much finer grained than others, with small white porphyritic felspars ;

both white and black mica, the latter in larger plates. Teign Valley.--Brownish-grey : this is a gneissose rock from a

boulder in the river bed near Newton-query if local. It is distinctly foliated, with black mica, and much of the quartz in

pale yellow crystalline bands. Torry Valley.—Red and black: red felspar in a sub-crystalline

base of quartz and schorl; the felspar crystals are small and do

not vary greatly in size. Trowlesworthy Tor, (Plym Valley.)-Red, black, and violet : not

seen in situ ; this is the rock which has been called trowlesworthite; it is mainly composed of red felspar, black schorl, and

violet fluor spar. Trowlesworthy.—Red and warm-grey : junction between a some

what coarse sub-crystalline schorlaceous granite and a finegrained vein, the latter in part porphyritic and traversed near the junction by five dark stripes approximately parallel to the undulations of the junction and each other, caused by the impersistent deposition or segregation of fine schorlaceous matter. There is a stronger schorlaceous vein in the granite corres

ponding Trowlesworthy.-Bright red : a pegmatite in which the felspar

largely predominates over the quartz, and schorl is not prominent; some of the felspar shews well-developed crystallization, and there is an occasional patch from which the colour

seems to have been discharged. Trowlesworthy.-Red and black: matrix of felted and acicular

schorl enclosing red felspars, occasionally fairly crystalline in

form. Trowlesworthy.—Dull red : granular schorlaceous pegmatite, fine

texture; the base mainly felspar, in which quartz granules and

fine schorl are generally distributed. Trowlesworthy.---Red: a schorlaceous pegmatite; felspar mostly

massive, with irregularly distributed quartz; not much schorl. Trowlesworthy-Red : a coarse but even-textured schorlaceous

granite with both white and black micas. Two Bridges (West Dart).-Pink: a fine-grained pegmatite thickly

sprinkled with schorl. Two Bridges. — Warm - brown : fine even - textured granular

pegmatite, with a small quantity of schorl. Two Bridges (West Dart).—Pink : the mass of this rock is a

beautiful flesh-coloured sub-crystalline felspar, with a small quantity of schorl in patches and pseudomorphic forms.

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Ugborough Beacon-Grey: granular-crystalline granite with a

little schorl; yellow talcose mica. Ugborough Beacon.—Speckled black and light pink: a schorlite with porphyritic quartz and small crystals of pink felspar, and occasional large well-formed crystals of the latter, ranging to an inch and a half in length; the felspars are mostly kaolinized and the disappearance of some has left cavities—others are

replaced by an undefined greenish-yellow saccharoid material. Ugborough Beacon.-Yellowish - brown : a saccharoid highly

— quartzose elvan, with irregular development of massive quartz,

and partial cavities containing quartz needles. Ugborough Beacon.—Pink weathering to a lighter shade: massive vitreous felsite developing quartz and felspar porphyritically,

with aggregates and needles of schorl; vein an inch wide. Ugborough Beacon.-Cream : granular earthy felsite with quartz

blebs, and ill-defined small red felspars. Ugborough Beacon.—Pinkish - cream : contact compact quartzose

felsite developing quartz blebs, with well-formed needles of

schorl. Walkham Valley.-Warm-grey: a granular felsitic rock mainly

composed of quartz and mica, with porphyritic felspars ; might

almost be called a porphyritic griesen. Walkhampton.--Grey: a very fine and even textured schorlaceous

pegmatite. Walkhampton.—Pink : felspathic pegmatite with arborescent

schorl. Walkhampton-Red: an even-textured schorlaceous felsite with a

tendency to porphyritic development of felspar and quartz. Whitleigh (Tamerton Foliott)-old building, possibly from a local

elvan.-Bluish-grey: compact sub-vitreous matrix with frequent quartz crystals and blebs and the cavities from which they have disappeared—the latter most common; also porphyritic felspar; some of the cavities contain ferruginous matter, others are lined with fine scaly micaceous or talcose material; there is a slender prism of what is probably schorl but may be hornblende, and in one of the cavities some very delicate acicular matter. No doubt, if not identical, this is essentially the same as the Roborough elvan, so largely used in the Middle Ages in the

Plymouth district as a free stone. Whitleigh (ditto).- Warm-grey : felsite with compact base, and

a few quartz blebs and crystals, with frequent cavities whence quartz and felspar crystals have disappeared-many of these

contain red and yellow ochreous matter. Widdecombe-in-the-Moor.-Red : coarse felspathic pegmatite, with

crystalline felspars.

Wigford (Meavy).—Grey with a greenish cast : a griesen, composed

of nearly equal quantities of white mica and quartz; the texture

somewhat open. Wigford Down (Meavy).—Pale brown : felsite, developing quartz

porphyritically, with fine open semi-honeycomb texture ; some of the cavities are caused by the disappearance of crystalline matter, others resemble minute vesicles; base mainly quartzose,

saccharoid texture. Winford (Meavy Valley).—Red : massive felspar, passing at times

into crystalline condition; contains a little schorl, less quartz,

and a casual fleck of mica. Winford.—Orange - brown : fine even grain with porphyritic

felspars, generally of a buff colour lighter than base, some however darker and of a pale red; occasional porphyritic quartz;

abundant black mica. Winford.—Red : massive felspar, sub-crystalline, with some fair

sized plates of black mica. Yannadon (Meavy).—Brown-grey : a schorlaceous greisen. Yannadon.- Pinkish-grey: an irregular mixture of felspar, quartz,

and earthy schorl. Yannadon.—Pink and black : a fine - textured luxulyanite with

porphyritic quartz. Yannadon-Grey: porphyritic schorlaceous granite with black and

bronze micas; base moderately coarse crystalline-granular with slight porphyritic development of quartz blebs ; some of the porphyritic felspars of considerable size; some ferruginous

matter. Yealm Head (near).—Dark grey with light porphyritic felspars.

The base of this rock is compact and may be described as subvitreous, in parts apparently inclined to be vesicular.

The porphyritic felspars are abundant, varying considerably in size and fairly well formed; they are chiefly cream-coloured and opaque, of ordinary type, but glassy varieties are also present. Porphyritic quartz in blebs is present in quantity. There is a little black mica. The rock appears to contain patches of more definitely granitic matter. It is highly interesting from the

number of characters combined. Yes Tor.-Pale-red : uneven-textured slightly porphyritic granite

with black mica ; rather coarsely granular. Yes Tor.Dull - drab: much like preceding, but mica more

prominent and less porphyritic felspar. Yes Tor (from clitter)—Brownish-grey: crystalline-granular texture,

casually recalling the aspect of a coarse sandstone; chief constituent felspar, with a fair amount of quartz, and a few flecks of mica; schorl chiefly in nests, in which either quartz or felspar are commonly more definitely developed.

The following is a list of the granites, felsites, and porphyritic rock fragments identified by me in the red breccias of Teignmouth, Dawlish, Exminster, Crediton, and Heavitree, the bulk of which are certainly, and the whole of which are probably, of kindred and Dartmoor origin. Coarse-grained granite with porphyritic felspars, partly kaolinized,

differs from ordinary coarse-grained Dartmoor granite only in its

reddish colour. Fine-grained schorlaceous granite, probably from a small vein or

boss. Exminster. Pegmatite, apparently vein : quartz with some well crystallized

felspar. Teignmouth. Quartz-felspar vein, with decayed mica and kaolinized felspar.

Exminster. Reddish quartz-felspar rock. Teignmouth. Reddish-grey glassy quartz-felsite. Teignmouth. Grey spherulitic felsite, with porphyritic quartz, slightly vesicular.

Teignmouth, Grey quartzose rock of trachytic aspect, semi-porous texture; base

appears like an open granular felsite; contains remains of decayed porphyritic felspars, quartz blebs, and little nests of black mica.

Teignmouth. Dark-red rock, presenting much the same general characters.

Teignmouth. Reddish-grey granular open-textured rock, with blebs of quartz,

mica-nests, and felspar-cavities lined and partly filled with kaolin;

some red iron-oxide in irregular cavities. Teignmouth. Grey granular rock of trachytic aspect, with some porosity;

cavities with remains of kaolinized felspars ; decayed mica; a

little differentiated quartz. Teignmouth. Pinkish-brown felsite, rough texture, slightly vesicular; por

phyritic felspars ; fluxion-structure indicated. Teignmouth. Somewhat similar rock with quartz-blebs ; cavities with kaoli

nized matter; some white mica ; porous rather than vesicular.

Teignmouth. Yellowish-brown quartz-porphyry, loose-textured subvesicular base,

with quartz-blebs and developing felspars in part kaolinized ;

matrix very porous in parts, yet heavy; a little mica. Dawlish. Greenish rhyolite or liparite with compact base, and large cavities,

elongated in direction of flow; occurs in wall at Teignmouth :

and is no doubt from conglomerate. Finely-vesicular rhyolitic rock with compact semivitreous green-grey

base; porphyritic quartz and felspar, the latter partly kaolinized; nests of mica; shows distinct fluxion-structure. Teignmouth.


Earthy-textured red and grey felsite with porphyritic felspars, nests

of mica, and vesicles partially filled with kaolin. Teignmouth. Red felsite with porphyritic quartz and felspar, quartz pre

dominating. Torbay. Vesicular felsite (“ horny” base) with porphyritic quartz, mica,

and felspar; full of irregular cavities. Red porphyritic felsite with quartz, kaolinized felspar, a little mica;

somewhat open-textured. Torbay. Reddish coarse-grained porous variety, with mica more prominent;

shows flow-structure. Compact red felsite with porphyritic quartz, felspar, and mica.

Heavitree. Pinkish-grey felsite, subvitreous base, with porphyritic quartz and

felspar, the latter partly kaolinized; has a decidedly rhyolitic

look. Heavitree. Granular red felsite, porphyritic quartz and felspar; some decayed

mica. Heavitree. Pinkish crystalline-granular felsite with porphyritic quartz and

felspar; small flakes of mica. Crediton. Porphyritic red and white quartz-and-felspar rock, apparently a

vein in felspathic trap. Crediton. Grey-green finely-granular felsite, with porphyritic quartz, kaolinized

felspar and some decayed mica. Crediton. Fine-grained crystalline-granular felsitic rock. Exminster. Reddish-grey quartzose felsite. Exminster. Dull brown porphyritic rock, felsitic base with kaolinized por

phyritic felspars, murchisonite, quartz, and mica; closely allied to the so-called red “porphyritic trap" more or less characteristic of the breccias and conglomerates from Torbay to the Crediton valley-a deep red porphyritic rock varying to red-brown and purplish-brown; compact felsitic base with porphyritic quartz and felspar, some kaolinized, some murchisonite-occasionally but not invariably some mica. This is really a porphyritic elvan

traversing alike granites and felspathic traps. Red sub-vitreous felsite, with porphyritic quartz and felspar and

some mica. Exminster. Pink fine-grained felsite, with occasional differentiation of quartz

and felspar. Heavitree. Granular schorlaceous pegmatite. Exminster, Teignmouth. Reddish compact felsite with blebs of quartz, a little mica, and

schorl pseudomorphous after felspar, and in spots. Exminster. Variety of same rock, with somewhat granular texture, por

phyritic quartz, decayed felspars, and veined with schorl. Exminster.

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