THE AUCHENORRHYNCHOUS HOMOPTERA. 65 



grounds. Ik the forms akin to Z/Cf^?-a^ueh as Petalocera hohe- 

 manni, ^tiilpEpicUnes planata, F., iina^roranus adspersipetmis, 

 Stal, the posterior tibiae are quadricarinate, compressed, and the 

 posterior margins spinose, the latter being especially notable in 

 the last-named form ; the cultrate form occurring in'^edra is 

 only a strong compression, so that the outer^urface has dis- 

 appeared as such. Th^ cheeks {gence) are va'^Ijedra aurita, L., 

 somewhat expanded, iw-Petc^cei'a and mstny of the related forms - 

 ■^Titwia, ^ik\; Titia, Stalj-Sic/itea, ^ivtA^Ilubria, Sttil (according 

 to Stal's statement in Hem. Afr.) — " very sliditly dilated " ; and 

 the last-named genus seems to lead over tcr^eropJdoea, Germ., 

 which is a good Jassine with somewhat expanded cheeks. The 

 antennae in ijedra aurita are also (see above) formed as in the 

 ^ Jassinse, and by no means resemble the antennae in that Mem- 

 bracine-form, in whose neighbourhood Ledra should probably 

 stay, vizr ^thalion, ha.tr.'^^ Ulopa diverges, on the contrary (see 

 later on), essentially from Jassinae, and must pass over t(P\lem- 

 bracinae, but after the removal of this genus the 0"assinaB in the 

 above-given circuit seem to me to be a very natural division — a 

 " Subfamily," characterized by the more or less dilated cheeks, the 

 typical quadricarinate, compressed (sometimes cultrate) posterior 

 tibiie (and the slender antennal whip, which, however, is not an 

 exclusive character). v^ 



The remaining part of the family Jassidae may perchance be 

 comprised as one division, ^lembracinae. It is, as regards the 

 structure of the head, antennae, and posterior legs, far more 

 multifarious than the ^assinae ; one can scarcely find positive 

 characters for it as a whole, and it ought perhaps, as proposed 

 by Stal, to be separated into several groups equivalent with 

 "^ Jassinae ; but most of these groups will probably not coincide 

 with Stal's " Subfamilies." 



A character probably met with in all the forms, and binding 

 them together, can be expressed thus : " cheek^scarcely or not at 

 all dilated.'' A group of the'^Membracinae — the'^" Hoplophorida," 

 Stal — is characterized by the arranger (Hem. Afr. p. 82), "pos- 

 terior tarsi small, shorter than the anterior pair"; but it is not 

 quite so sharply expressed as it could be, as their posterior tarsi 

 are in reality far thinner and nearly double as short as, for 

 example, the intermediate tarsi ; and besides, this character is 

 not exclusive, for I am acquainted with forms, which certainly 

 in every way are referable to the subfamily '^" Membracida," 

 Stal, in which the posterior tarsi are clearly shorter and more 

 slender than the other pairs, to almost as great a degree as in the 

 ^/*' Hoplophorida." On the other hand, the group certainly shows 

 always a character peculiar to it, viz. the posterior tibiee are for 

 the greatest part of their length considerably compressed obliquely, 

 and towards the ajjex curved first of /ill inivards and then again 

 outwards. In the above-mentioned ''Membracis-forms with the 



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