370 



FOREST ENTOMOLOGY. 



brief account of them is intended only for a formal introduction to the 

 family as associated with forest trees. 



It has been remarked that they are very closely allied to Aphididse, 

 hence Buckton adopts the term Tettigidce. The following table, 1 which 

 is perhaps chiefly of a microscopical character as regards tarsal struct- 

 ure, may therefore be given viz. : 



Order RHYNCHOTA. 

 Sub- Order HOMOPTERA. 



I 

 Section I. 



Monomera (Westw.) 



Section II. 

 Dimbra (Westw. 



Aleyrodinte. 



Aphidinse. 



COCCIDiE. 



Section III. 

 Trimera (Westw.) 



Psyllidse. 



Thripida?. 



TETTIGID.E. 



In size the British Cicadidse show a considerable resemblance to the 

 Aphididae, but the most striking contrast is with regard to the wings, 

 which are coriaceous, more especially the upper wings or elytra. This 

 characteristic almost obliterates the venation. The under wings are 

 also coriaceous, but not so dense as the upper. 



The head is always more rounded than in the case of the Aphididse 

 in fact, it may be termed frog-shaped. The antennae are never very 

 long : they are extremely slender, so much so that even under the 

 microscope the joints are very difficult to count. 



The insect feeds by means of a short proboscis, which is variable in 

 length but always three-jointed. 



No cornicles are ever found on the body, nor any organs for secret- 

 ing special exudation as a protective covering. 



The legs contrast with the Aphididae, inasmuch as they are well 

 adapted for leaping, the femorse and coxae having powerful muscles. 

 The tarsi are three-jointed, but this is sometimes rather difficult to 

 determine by observation. 



1 From Monograph of the British Cicadse or Tettigidte, by George Bowdler 

 Buckton, vol. i. p. xxxiv. 



