[Illustration: PTYCHOPTERA PALUDOSA LIMNOBIA REPLICATA _From enlarged photographs, made at the Yorkshire College, Leeds, from specimens bred by the Author, and mounted by Messrs. Watson & Son, High Holborn, London_] THROUGH A POCKET LENS BY HENRY SCHERREN, F.Z.S. AUTHOR OF ‘PONDS AND ROCK POOLS,’ ‘A POPULAR HISTORY OF ANIMALS,’ ETC. _WITH NINETY ILLUSTRATIONS_ THE RELIGIOUS TRACT SOCIETY 56 PATERNOSTER ROW AND 65 ST. PAUL’S CHURCHYARD 1897 Oxford HORACE HART, PRINTER TO THE UNIVERSITY CONTENTS CHAPTER I. PAGE THE POCKET LENS, THE DISSECTING MICROSCOPE, AND SOME SIMPLE APPLIANCES 11 CHAPTER II. ARTHROPODS AND THEIR CLASSES.--THE MARGINED WATER BEETLE; THE GREAT WATER BEETLE; THE COCKTAIL BEETLE 27 CHAPTER III. COCKROACHES; EARWIGS; THE GREAT GREEN GRASSHOPPER; THE WATER SCORPION; THE WATER BOATMAN; CORIXA 63 CHAPTER IV. SPIDERS, MITES, AND MYRIAPODS 96 CHAPTER V. CRUSTACEANS.--PRAWN, SHRIMP, MYSIS, CRABS; AMPHIPODS; ISOPODS 128 CHAPTER VI. AQUATIC INSECT LARVAE 157 INDEX 189 LIST OF ILLUSTRATIONS FIG. PAGE _Ptychoptera paludosa. Limnobia replicata_ _Frontispiece_ 1. Hand Magnifier and Stand 14 2. Zeiss’s Dissecting Microscope 16 3. Leitz’s Dissecting Microscope 17 4. Two Leitz Lenses in holder (open) 18 5. Two Leitz Lenses in holder (closed) 18 6. Home-made Dissecting Microscope 19 7. Beakers 21 8. Glass Capsule 21 9. Glass Block, with cover 22 10. Glass Box, with cover 22 11. Forceps 23 12. Three forms of Dipping-tube. Method of using it 24