CONTENTS. 



-♦o*- 



Introduction . ..... Pa^es 1-7 



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CHAPTER I. 



HABITS OF WORMS. 



Nature of the sites inhabited — Can live long under 

 water — Nocturnal — Wander about at night — Often 

 lie close to the mouths of their burrows, and are 

 thus destroyed in large numbers by birds — Structure 

 — Do not possess eyes, but can distinguish between 

 light and darkness — Retreat rapidly when brightly 

 illuminated, not by a reflex action — Power of atten- 

 tion — Sensitive to heat and cold — Completely deaf 

 — Sensitive to vibrations and to touch — Feeble 

 power of smell — Taste — Mental qualities — Nature 

 of food — Omnivorous — Digestion — Leaves, before 

 being swallowed, moistened with a fluid of the 

 nature of the pancreatic secretion — Extra-stomachal 

 digestion — Calciferous glands, structure of — Cal- 

 careous concretions formed in the anterior pair of 

 glands — The calcareous matter primarily an excre- 

 tion, but secondarily serves to neutralise the acids 

 generated during the digestive process . 8-56 



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