CONTENTS 
lx 
CHAPTER VI 
THE COLOURS OF CRUSTACEA AND ECHINODERMA 
Nature of Colours of Crustacea—Colour Variation — Pigments of 
Crustacea: (i) Lipochromes, (2) Soluble Blues—Relations of 
the Two—General Characters of Pigments — The Colours of 
Echinoderma : (1) Star-fishes, (2) Brittle-stars, (3) Sea-urchins, 
(4) Crinoids, (5) Holothurians — Pigments of Five Classes — 
Relations to those of Crustacea . . . Page 117 
CHAPTER VII 
THE COLOURS OF THE LEPIDOPTERA 
Insect Coloration and its General Relation to Physiology—Pigments 
of Caterpillars—Intrinsic and Derived Pigments—Mr. Poulton’s 
Experiment—Meaning of Derived Pigments—Other Characters 
of the Coloration of Caterpillars—Colours of Butterflies, Pig¬ 
mental and Optical Colours—The Pigments of the Pieridae— 
Pigments of other Butterflies—Origin of the Pigments of Butter¬ 
flies—Contrast between the Pigments of Butterflies and those of 
Caterpillars—Pigments and Mimicry . . .138 
CHAPTER VIII 
THE COLOURS OF INSECTS IN GENERAL AND OF SPIDERS 
Optical and Pigmental Colours in Insects—Colours of the different 
Orders of Insects—Colours and Pigments of Orthoptera—Optical 
Colours of Neuroptera — Coloration of Beetles — Pigments of 
Hemiptera—Colour Resemblances between Diptera and Hymen- 
optera—Contrast between Coloration of Lepidoptera and other 
