ENTOMOLOGY. 



393 



The head is usually broad, with horns commonly of moder- 

 ate length, composed of three to five joints ; mouth suctorial, 

 but placed in front of the lower part of the head. 



1 and 2, Potato Bug [Lygus solani) : 3'ancT 4, pupa, nat. size aud magnified; 

 5, Hop Bug, nat. size ; 6, ditto, magnified. 



Horns usually somewhat thread-like. Legs various, chiefly 

 formed for walking, but sometimes in the aquatic species with 

 fringes on the hinder pair. 



Larvffi resemble the perfect insect, but without rudiments 

 of wings ,* pupae with still more resemblance, from these being 

 distinguishable. 



One section of this Order lives in water, and contains the 

 insects commonly known as Water Scorpions and Water Boat- 

 men ; the other, besides the " Water Measurers " common on 

 water, contains various kinds of Bugs preying on plant and 

 animal life by means of their suckers, and characterised 

 generally by a power of giving out a scent on being alarmed, 

 which is usually, but not always, of a disagreeable kind. 



12. APHANIPTEEA (Kirby).— Fleas. 



Flea, maggot, and pupa, magnified ; lines giving nat. length. 



Four scales, which are '' inqKrccptihle" to the naked eye, 



