PART I

STRUCTURE, FUNCTIONS, AND DEVELOPMENT OF ANIMALS

I.--THE STUDY OF ANIMALS AND THEIR LIFE.

Our familiar knowledge of animals and their life, 1.--Zoology and its divisions, 2.--A first course in Zoology, 3.

II.--THE GARDEN TOAD (BUFO LENTIGINOSUS).

[Laboratory exercise], 5.--External structure, 5.--Internal structure, 7.

III.--THE STRUCTURE AND FUNCTIONS OF THE ANIMAL BODY.

Organs and functions, 14.--The animal body a machine, 14.--The essential functions or life-processes, 15.

IV.--THE CRAYFISH (CAMBARUS SP.).

[Laboratory exercise], 17.--External structure, 17.--Internal structure, 21.

V.--THE MODIFICATION OF ORGANS AND FUNCTIONS.

Difference between crayfish and toad, 26.--Resemblances between crayfish and toad, 27.--Modification of functions and structure to fit the animal to the special conditions of its life, 29.--Vertebrate and invertebrate, 30.

VI.--AMŒBA AND PARAMŒCIUM.

[Laboratory exercise], 31.--Amœba, 31.--The slipper-animalcule (PARAMŒCIUM SP.), 34.

VII.--THE SINGLE-CELLED ANIMAL BODY; PROTOPLASM AND THE CELL.

The single-celled animal body, 36.--The cell, 37.--Protoplasm, 39.

VIII.-CELLULAR STRUCTURE OF THE TOAD (OR FROG).

[Laboratory exercise], 40.--The blood, 40.--The skin, 40.--The liver, 41.--The muscles, 41.

IX.--THE MANY-CELLED ANIMAL BODY; DIFFERENTIATION OF THE CELL.

The many-celled animal body, 43.--Differentiation of the cell, 43.

X.--HYDRA.

[Laboratory exercise], 46.

XI.--THE SIMPLEST MANY-CELLED ANIMALS.

Cell-differentiation and body-organization in Hydra, 52.--Degrees in cell-differentiation and body-organization, 54.

XII.--DEVELOPMENT OF THE TOAD.

[Field and laboratory exercise], 55.

XIII.--MULTIPLICATION AND DEVELOPMENT.

Multiplication, 57.--Spontaneous generation, 58.--Simplest multiplication and development, 59.--Birth and hatching, 61.--Life-history, 62.