Subvar. h. Flaggy.

Var. d. Slate.

Subgroup C. Fault rock.

i. Conglomeritic.
j. Nodular.

k. Concretionary.
1. Spheroidal.
m. Lenticular.

n. Mudstone.

o. Tutenic shale.

Subvar. a. Roofing slate.

b. Slab slate.

c. Pencil slate.

d. Novaculyte.

e. Calcareous slate.

f. Carbonaceous.

g. Arenaceous.

h. Tuffose.

i. Ribaned.
j. Conglomeritic.

Group B.-ROCKS FOR THE MOST PART CHEMICALLY FORMED.

I. Minerals occurring as rocks (see page 17).
Var. a. Asphalte.

b. Pyrite.

c. Cinnabar.

d. Boracite.
e. Trona.

f. Aragonite.
g. Manganese ores.
h. Rhodochrosite.
i. Bole.

j. Opal.

k. Fluorite.

7. Barite.

m. Ankerite.
n. Malachite.
o. Melanite.

p. Galmey.
q. Zincite.

r. Galenite.

s. Stibnite.

t. Arsenopyrite.

u. Sulphur.
v. Wavellite.

w. Chalcopyrite.

Group C.--ROCKS PARTLY MECHANICALLY, PARTLY CHEMICALLY.

AND PARTLY ORGANICALLY FORMED.

Subgroup A. Laminated, or stratified coal.

Subvar. a. Caking coal.
b. Non-caking coal.
c. Cherry coal.

Var. d. Anthracyte.

Subvar. a. Native coke.

Subgroup B. Surface deposits and accumulations.

Var. a. Boulder-clay-drift.

Subvar. a. Calcareous.