HISTOLOGY OF
MEDICINAL PLANTS
BY
WILLIAM MANSFIELD, A.M., PHAR.D.
Professor of Histology and Pharmacognosy, College of
Pharmacy of the City of New York
Columbia University
TOTAL ISSUE, FOUR THOUSAND
NEW YORK
JOHN WILEY & SONS, INC.
LONDON: CHAPMAN & HALL, LIMITED
Copyright, 1916, by
WILLIAM MANSFIELD
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
CHAPTER V
CONDUCTING TISSUE
Vessels and tracheids 126
Annular vessels 127
Spiral vessels 127
Sclariform vessels 128
Reticulate vessels 131
Pitted vessels 131
Pitted vessels with bordered pores 131
Sieve tubes 136
Sieve plate 138
Medullary bundles, rays and cells 138
Medullary ray bundle 139
The medullary ray 139
The medullary ray cell 141
Structure of the medullary ray cells 142
Arrangement of the medullary ray cells in the medullary ray 142
Latex tubes 142
Parenchyma 144
Cortical parenchyma 147
Pith parenchyma 147
Leaf parenchyma 150
Aquatic plant parenchyma 150
Wood parenchyma 150
Phloem parenchyma 150
Palisade parenchyma 150
CHAPTER VI
AERATING TISSUE
Water pores 151
Stomata 151
Relation of stomata to the surrounding cells 154
Lenticels 157
Intercellular spaces 158
CHAPTER VII
SYNTHETIC TISSUE
Photosynthetic tissue 163
Glandular tissue 164
Glandular hairs 164
Secretion cavities 166
Schizogenous cavities 168
Lysigenous cavities 168
Schizo-lysigenous cavities 168
CHAPTER VIII
STORAGE TISSUE
Storage cells 173
Storage cavities 176
Crystal cavities 176
Mucilage cavities 176
Latex cavities 176
Oil cavity 178
Glandular hairs as storage organs 178
Storage walls 179
CHAPTER IX
CELL CONTENTS
Chlorophyll 182
Leucoplastids 183
Starch grains 183
Occurrence 184
Outline 185
Size 185
Hilum 185
Nature of hilum 188
Inulin 194
Mucilage 194
Hesperidin 196
Volatile oil 196
Tannin 196
Aleurone grains 197
Structure of aleurone grains 197
Form of aleurone grains 197
Description of aleurone grains 198
Tests for aleurone grains 198
Crystals 200
Micro-crystals 200
Raphides 200
Rosette crystals 202
Solitary crystals 205
Cystoliths 210
Forms of cystoliths 210
Tests for cystoliths 215
PART III
HISTOLOGY OF ROOTS, RHIZOMES, STEMS, BARKS,
WOODS, FLOWERS, FRUITS AND SEEDS
CHAPTER I
ROOTS AND RHIZOMES
Cross-section of pink root 219
Cross-section of ruellia root 219
Cross-section of spigelia rhizome 223
Cross-section of ruellia rhizome 226
Powdered pink root 227
Powdered ruellia root 227