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THE STUDENTS MANUAL

II. MORPHOLOGY.

1. THE CELL: the unit of structure 355.

a Cellulose: cell-wall 357.

b Protoplasm: the living substance of the cell 1554.

c Karyokinesis: cell division 993; as in diatoms 527; and nostoe 492. (1) Meristem or formative tissue 1207.

(1) The nucleus 1365.

(2) The cytoplasm

493.

2. THE SPORES: special cells for reproduction 1803.

b Asexual spore:

— formed b y cell division 117.

c Sexual spore : formed by union of cells 1730.

a The Archesporium: which sets apart certain cells for reproduction 91.

(1) The sporangium: in

which the spores are formed 1803.

(2) The tetrad forma-

tion: four sister spores 1894.

(1) The gametes: or

sexual cells 735.

(2) The antheridium:

or male organ 78.

(3) The archegonium:

or female organ 91.

(4) The sperm: the

male cell 1796.

(5) The oosphere: the

female cell 1385.

(6) The oospore: or fer-

tilized egg 1385.

3. ALTERNATION OF GENERATION: 55.

d, Heterospory: in which the gametes are unlike 871.

fa. Gametophytes: the generation producing sex-organs 55; apogamy 83.

b. Sporophytes: the generation producing asex-

ual spores 1804; apospory 83.

c. Homospory: in which the gametes are alike

883.

(1) Microspores: pro-

ducing male ga-metophyte 1221; microsporangium 1221.

(2) Megaspores: pro-

ducing a female g a m e t o p h y te 1199; megaspo-rangium 1199.

4. THE SEEDS: which produce the flowering plants 1718.

(1) The testa: or hard coat upon which hairs and wings grow 1894.

{(a) Cotyledons: the first leaves developed 465. (b) Hypocotyl: the stem-like portion beneath 907.

(3) The endosperm: food tissue within em-

bryosac 614.

(4) The perlsperm: food tissue outside embry-

osac 1452.

2268

a. Parts of the seed: