xvi CONTENTS 



hosts to complete their life-cycle — The sheep-ticl< — Various 

 animal parasites, beneficial and otherwise — Study of parasites 

 offers a prodigious field for scientific worl< . Pp- i57~i^3 



CHAPTER VIII 



INSECT WEAPONS AND TOOLS 



Many insects which can inflict serious injury with their weapons 

 — The f,'ad-fly — Personal experience of the effect of its 

 weapons — The malarial mosquito — The weapons of the 

 wasp — The spider's poison fangs and teeth — A fly's foot — 

 The foreleg of a diving beetle — Feathered oar of a water- 

 boatman — Poison bag and sting of wasp — An insect armed 

 with a bayonet — The saw-fly's weapons — Ever)- insect has 

 some special weapons to suit its own particular purposes 



Pp. 184-206 



CHAPTER IX 



MAY-FLIES AND THEIR NEIGHBOURS 



Insect life at the bottom of the pond — Aquatic insects spend the 

 greater part of their lives beneath the water — The May- fly 

 as the type of brief and ineffectual life — Their anatomv — 

 Their graceful and buoyant movements — Life story — Extra- 

 ordinary final emergence — The alder-fly — Caddis-flies — The 

 wonderful cases built by the caddis-grubs — Dragon-flies — 

 Mask of the dragon-fly larva — Strength of wings — Eating 

 butterfly ....... Pp. 207-233 



CHAPTER X 



WONDERFUL FEETH AND TONGUES 



The mouth of a snail is provided with teeth unlimited — Genera 

 and species identified by the various characteristic dental 



