Feb., 1892. 
PERMIAN BRECCIA OF LEICESTERSHIRE. 
29 
at the N.W. end of Cliarnwood, and has probably come from 
that series. (50.) A hard breccia of volcanic fragments, which 
under the microscope are seen generally to be rather angular ; 
they appear often to be stained by subsequent infiltration of 
iron oxide, so that in the case of the more compact it is 
difficult to say whether they are a decomposed volcanic glass 
or a mudstone ; but undoubtedly three or four varieties of 
igneous—almost certainly volcanic—rocks are present. In 
one, a porphyrite (?), larger crystals, about *03in. diameter 
are present, together with a dull green, feebly refracting 
mineral, of which there are two or three larger patches in 
the slide; this, probably, replaces a pyroxenic constituent. 
In this fragment one or two of the larger crystals are curious. 
They resemble felspar in form, and partly in appearance, but 
seem to consist mainly of a polysynthetic quartz. There is 
also a fragment in the slide which may have a similar origin. 
It is possible that some of the materials in this breccia may 
have come from the Cliarnwood series, but the resemblance is 
not striking. (45.) A fragment, in part angular, in part some¬ 
what rounded, of a rock which consists of compact green and 
of rather gritty light-red bands, with a faint cleavage. 
Under the microscope, the coarser band is seen to contain a 
large number of felspar crystals, whole and in fragments, the 
matrix and the remainder of the slide consisting of fine¬ 
grained material, occasionally ferrite-stained, probably 
volcanic dust. This is most probably from the Cliarnwood 
series. (93.) A fragment, with corners somewhat rounded, of 
a banded, fine-grained volcanic grit. Of the likeness of this 
rock to one of the Cliarnwood series I cannot speak quite so 
confidently. (5.) A rock containing a large number of felspar 
fragments, more or less decomposed, together with some 
irregular patches of a green colour, set in a dark, earthy- 
looking, sometimes greenish or brownish paste, the material 
being arranged in bands of coarser and finer. Granules of 
black iron oxide are present. The green patches probably 
consist of a kind of viridite or palagonite, replacing a glassy 
basic material; now and then a rather decomposed felspar 
crystal can be detected in it. Probably they represent frag¬ 
ments of a rather basic lava. This rock possibly may be 
from Cliarnwood, but the resemblance to those known to 
occur in that district is not striking. (104.) A specimen, with 
rounded edges, from Stanton, of a banded ashy grit, somewhat 
like Nos. 5 and 45. (63.) A flattish fragment, with edges 
and angles somewhat rounded, consisting of a hard, greenish 
argillite or imperfect slate (striated). Most probably from the 
Cliarnwood series. (84.) A fragment, with slightly worn 
edges, of a somewhat banded argillite of greyish-green colour, 
