THE AUCHENORRHYNCHOUS HOMOPTERA. 335 



f. 6 a) are very distinct on the anterior side of the basal portion. 

 The articulating membrane is, with the exception of the spot on 

 the proximal point of the coxae, well developed, and is remarkably 

 broad on the inner side of the articulation. Consequent on this 

 articulation, the coxae can perform two kinds of movements : in 

 part they can turn on an axis, which forms a very acute angle 

 with their own long axis, and with this turning the apices of the 

 femora move in a part of a semicircle from behind forwards and 

 inwards (and vice versa) ; in part this distal portion is able to 

 move, on turning around on an axis perpendicular to the longi- 

 tudinal direction of the coxae, somewhat backward and inward, 

 somewhat forward and outward, {adduction and abduction), whence 

 it follows that the tarsi are able to extend farthest outwardly, 

 forward or behind, when the coxae are "abduced." 



In tl^'e^ Strididantia the anterior femora are very thick, and 

 generally toothed beneath ; the trochanters are thick, supporting 

 {viz. connected with) the femora by a very oblique articulation, 

 which presents a very well developed see-saw movement. In the 

 other three families the anterior femora are usually not very 

 thick, and unarmed. Trochanters supporting, normal ; only in 

 ^ Dar7iis have I found both anterior (and intermediate) femora 

 strongly dilated. 



b. Intermediate Legs. 1. Stridulantia. 



The coxae are moderately short, broad, and obliquely tri- 

 angular at the base, with an articulation which is quite as long 

 as the coxae, and the (ulterior angle of the articulation is situated 

 moderately near to the insect's middle plane. The coxae are some- 

 times in the middle plane contiguous at their moderately short, 

 free, distal part ; this is often, however, not the case, for in 

 ^ Platypleura the distance between them is somewhat considerable. 

 The principal movement is rotary, to and fro on an axis from the 

 exterior angle of the articidation to its ajitero-interior angle, almost 

 perpendicular to the insect's longitudinal axis ; moreover, a 

 rather feeble adduction and abduction is possible, arising from 

 the fact that the articulating membrane along the interior mar- 

 gin of the articulation is rather broad. A real " meracanthus^ 

 is not to be found, but the plate situated on the postero-exterior 

 margin of the coxae, from which it otherwise originates, is here 

 well developed. The trochanters are supporting, and the femora 

 normal as in the three families following : — 



2 and 3. Cercopida a.nd'^Jassid/e. — The coxae have a form 

 somewhat resembling that in the "^trididantia ; they are, how- 

 ever, quite as transversely situated and placed close together, so 

 that their free apical parts are contiguous in the middle plane ; their 

 ad- and abductorial movements are only feeble. A meracanthus is 

 very considerable, and strong in all Cercopidae ; it is wanting in 

 most Jassidae, but is, however, strong, long, and broad at the 



