668 PROF, T, G. BONNEY ON THE MICROSCOPIC 
(6) Woodgate quarry.—Rolled and subangularfragments of quartz, 
decomposed felspar, grit, and rhyolite or mudstone. There is also 
a large quantity of a streaky chloritic mineral, and many of the 
fragments appear to be stained with ferrite. Parts of the slide pre- 
sent some resemblance to organic structure, such as sponge-spicules; 
but, after repeated examination, I believe that they are rhyolitic 
fragments with crystallites of the form mentioned above (p. 663). 
(7) S.W. slope of Ragleth—This rock, which, macroscopically, 
appears to be a compact yellowish-grey mudstone with a few lighter 
spots, exhibits under the microscope a minute confusedly granular 
structure, being apparently composed of fine felspathic mud, stained 
with ferrite, in patches more or less irregular and containing a fair 
amount of opacite. Some rather acicular doubly refracting micro- 
liths may be of secondary origin, as are the felspathic (?) infiltrations 
of a crack. There is nothing characteristic about the rock, which 
might be of any age from Silurian downwards. 
(8) £. of Carwood—This rock is a good deal decomposed ; itappears 
to have undergone some brecciation in situ, and to have been re- 
cemented, quartz and epidote occurring in the cracks. It might bea 
decomposed rhyolite with a faintly marked flow-structure, or it 
might be an altered mudstone, the detritus of a rhyolite. I hesita- 
tingly incline to the former identification. 
(9) NE. of Hanter Hill—The specimen consists of quartz, 
felspar, a little of a chloritic mineral (probably replacing hornblende 
or biotite), and ferrite. The quartz is full of minute enclosures, 
which give it, in parts, a dirty aspect. These, on applying a high 
power, appear opaque, being probably earthy or ferruginous ; others, 
however, are transparent,—whether cavities or microliths of some 
mineral I cannot with certainty determine; some show a very mi- 
nute black speck, as if they were nearly full of a fluid. The felspar 
is much decomposed; probably it is chiefly orthoclase, but the 
characteristic banding of plagioclase is also visible. The rock is 
evidently of fragmental origin, one part of the slide showing many 
small grains and rather a different structure from the rest ; but it has 
been a good deal altered, and in general aspect recalls specimens of 
the granitoid Dimetian rocks which I have examined. 
West Field, Burcot.—A rhyolitic agglomerate, apparently wholly 
composed of volcanic material. Some of the larger fragments exhibit 
different varieties of fluidal structure, and one shows excellent per- 
litic structure. 
Lilleshall.T wo specimens, collected by myself about two years 
since, have been examined ; one (from the top crag on the S. flank 
of the ridge) is a rhyolitic agglomerate, like, but rather more de- 
composed than, those at the Wrekin described by Mr. Allport*. 
The other is a rhyolite (devitrified) with rather obscure indications 
of spherulitic structure. It occurs just 8. of the monument, and is 
probably part of a small coulée; but its relations to the other rocks 
are not very clear. 
As the result of the investigations above described, I should con- 
* Quart. Journ. Geol, Soc. vol. xxxiii. p. 458. 
