and review, to a series of questions appended to each

page.

Experience in teaching geology indicates that nothing so much encourages the pupil and facilitates his progress, as frequent use of sections on a large scale, to illustrate both the actual modes of occurrence of geological phenomena, and theoretical views. The map recently prepared by Professor Hall is admirably adapted to this purpose.

3

5 Agency of the ocean,

6 Gulf Stream,

Distribution of land and water, 7-its temperature,

anticlinal line, synclinal, 101 Classification of the unstrati-

Columnar structure; jointed, 107 Petrifiers,

127

128

129

Volcanic rocks; plutonic, 108 Requisite means for determin-

ing fossils; fundamental

principle of comparative

anatomy,

109

110 Number of fossils,

111

130

131

132

Marine, estuary, fresh water

and terrestrial relics,

Situation in which fossils were

formed; entire or broken, 133

112 Species, varieties; species be-

come extinct; genus, order,

kingdom, family and tribe, 134

Distribution of animate be-

ings in former periods,

Duration of families, genera,

and species,

113

Metamorphic rocks, their po-

sition, structure, origin,

Joints; master joints; their

direction and origin,

Cleavage; its constancy of

direction and origin,

Systems of classification-

their points of agreement;

of difference,

Age of rocks determined by

position, mineral character

and organic contents,

Difficulty of observing from

absence of some strata, . 114

Determination by fossils; spe-

cies not identical through-

out a formation,

Identity of mineral constitu-

tion does not prove rocks

contemporaneous,

Age of unstratified rocks de

termined by their relations

to the strata,

115

135

136

116

138

Fossils most unlike as they

1

Fossil botany; plants, cel-

lular, vascular, crypto-

gamous, phanerogamous,

monocotyledonous, dicoty-

ledonous, endogenous and

exogenous,

2140

141

142

Plants determined by ana-
tomical structure; leaves,
flowers, fruits, trunks and
secretions, fossil, .

Geological position of cellu-

lar plants, cryptogamous,

coniferæ, cycadeæ, endo-

genous and exogenous,

History of fossil vegetation

not complete; number of

fossil species now known, 143

Origin of the different forms,
anthracite, bituminous
and wood coals; bitu-
minization now occurring, 144
Fossil zoology; Cuvier's
classification; four divi-
sions,

Radiata, their structure;

echinodermata, sea-ur-

acalephæ, jelly

chins ;

fishes; polypi; sponges,

Mollusca, structure; cepha-

lopoda, acephala, gastero-

poda; univalve, bivalve,

multivalve and chambered

145

146

Coprolites,

Classification according to

animate types, protozoic,

mesozoic and cainozoic,

Prof. Agassiz' ages of na-

ture; reign of fishes, of

reptiles, of mammalia,

and of man,

CHAPTER IV.

8150

151

152

2153

THE UNSTRATIFIED ROCKS.

The igneous rocks consist of

feldspar and hornblende;

differ in structure as they

are cooled under slight or

great pressure,

Granitic rocks-their struc-
ture and position,

Granite, its characteristic

ingredients and colors;

graphic granite; porphy-

ritic,

Syenite; syenitic granite,

Porphyry, its ancient signi-

fication and present use,

154

155

156

157

Metaliferous veins, most

abundant in the oldest

strata; veinstone, gangue

or matrix; their produc-

tiveness influenced by

their direction,

Trappean rocks—significa-

tion of trap; origin, dif-

158

ference from granite, and

mode of occurrence,

159

Greenstone, constituents and

148 Basalt, constituents, color

and structure,

161

119 on adjacent rocks,

166