Chapter I: Preface

The object of the book is to provide a practical scientific course in vegetable histology for the use of teachers and students in schools and colleges.

The medicinal plants are studied in great detail because they constitute one of the most important groups of economic plants. The cells found in these plants are typical of the cells occurring in the vegetable kingdom; therefore the book should prove a valuable text-book for all students of histology.

The book contains much that is new. In Part II, which is devoted largely to the study of cells and cell contents, is a new scientific, yet practical, classification of cells and cell contents. The author believes that his classification of bast fibres and hairs will clear up much of the confusion that students have experienced when studying these structures.

The book is replete with illustrations, all of which are from original drawings made by the author. As most of these illustrations are diagnostic of the plants in which they occur, they will prove especially valuable as reference plates.

The material of the book is the outgrowth of the experience of the author in teaching histology at the College of Pharmacy of the City of New York, Columbia University, and of years of practical experience gained by examining powdered drugs in the laboratory of a large importing and exporting wholesale drug house.

The author is indebted to Ernest Leitz and Bausch & Lomb Optical Company for the use of cuts of microscopic apparatus used in Part I of the book.

The author also desires to express his appreciation to Professor Walter S. Cameron, who has rendered him much valuable aid.

WILLIAM MANSFIELD.

COLUMBIA UNIVERSITY,
September, 1916.

CONTENTS

PART I

SIMPLE AND COMPOUND MICROSCOPES AND MICROSCOPIC
TECHNIC

CHAPTER I

THE SIMPLE MICROSCOPES

PAGE

Simple microscopes, forms of 4

CHAPTER II

COMPOUND MICROSCOPES

Compound microscopes, structure of 7
Compound microscopes, mechanical parts of 7
Compound microscopes, optical parts of 9
Compound microscopes, forms of 12

CHAPTER III

MICROSCOPIC MEASUREMENTS

Ocular micrometer 19
Stage micrometer 19
Mechanical stage 21
Micrometer eye-pieces 21
Camera lucida 22
Drawing apparatus 23
Microphotographic apparatus 24

CHAPTER IV

HOW TO USE THE MICROSCOPE

Illumination 26
Micro lamp 27
Care of the microscope 28
Preparation of specimens for cutting 28
Paraffin imbedding oven 30
Paraffin blocks 31
Cutting sections 31
Hand microtome 31
Machine microtomes 32

CHAPTER V

REAGENTS

Reagent set 39
Measuring cylinder 40

CHAPTER VI

HOW TO MOUNT SPECIMENS

Temporary mounts 41
Permanent mounts 41
Cover glasses 43
Glass slides 44
Forceps 45
Needles 46
Scissors 46
Turntable 46
Labeling 47
Preservation of mounted specimens 48
Slide box 48
Slide tray 48
Slide cabinet 49

PART II

TISSUES, CELLS AND CELL CONTENTS

CHAPTER I

THE CELL

Typical cell 53
Changes in a cell undergoing division 55
Origin of multicellular plants 57

CHAPTER II

THE EPIDERMIS AND PERIDERM

Leaf epidermis 59
Testa epidermis 63
Plant hairs 66
Forms of hairs 67
Papillæ 67
Unicellular hairs 69
Multicellular hairs 72
Periderm 80
Cork periderm 80
Stone cell periderm 85
Parenchyma and stone cell periderm 85

CHAPTER III

MECHANICAL TISSUES

Bast fibres 89
Crystal bearing bast fibres 90
Porous and striated bast fibres 92
Porous and non-striated bast fibres 96
Non-porous and striated bast fibres 96
Non-porous and non-striated bast fibres 96
Occurrence of bast fibres in powdered drugs 103
Wood fibres 104
Collenchyma cells 106
Stone cells 109
Endodermal cells 116
Hypodermal cells 118

CHAPTER IV

ABSORPTION TISSUE

Root hairs 121