BY R. J. TILLYARD. 867 



Family SCYTINOPTERIDAE HandL, a me emendata. 



Primitive Homoptera belonging to the Upper Permian and 

 Trias, in which the veins R, M and Cn come off separately from 

 a point close to the base, and diverge from one another distad. 

 Sc may or may not be present as a separate vein. M and Cu x 

 are always forked, the former usually, the latter always towards 

 the distal part of the wing. Condition of R very variable. 



Clavus separated from rest of wing by a straight, deeply im- 

 pressed vena dividens (Cu 2 ). Veins of the clavus (1A, 2A), 

 standing far apart, 1A being waved, 2A very short, 3A usually 

 absent. Anal angle rounded. 



Tegmina of a tough, leathery consistency, finely tuberculated 

 or pitted all over in most genera, but sometimes (Chiliocyc!a) 

 armoured with large, closely-set, circular, flat tubercles, or quite 

 smooth (Permofulgor) . 



Key to the Subfamilies and Genera of the family 

 SC YTINOPTERI DAE . 

 I Tegmen very narrow and elongated, smooth ; clavus with threa 

 separate veins upon it. 



Subfam. PERMOFCTLGORINAE. 



n . (Only one genus, Permofulgor Till, from the Upper 



Permian of Belmont, N.S.W.) 

 Tegmen much broader in proportion, more or less tuberculated or 

 pitted; clavus with only two separate anal veins, placed wide 

 L apart. 2. 



I K with only two main branches, or not branched at all until near 



distal end. Subfam. SCYTINOPTEEINAE. 3. 



(Upper Permian and Upper Triassic) . 

 J R dividing into at least three main branches (venation of dis- 

 tinct Cixiid type). — Subfam. MESOCIXIINAE. 8. 



(Upper Trias of Ipswich, Q.) 



f Basal two-thirds or more of tegmen covered with large, flat, cir- 



(3) -<j cular tubercles, closely set together. Chiliocycla, n.g. 



i 



[Xo such tubercles present on tegmen. 4. 



f Area of tegmen between costa and R free of transverse veinlets 

 i from base to beyond half-way alon^; the wins. 5. 



i Area of tegmen between costa and R with a series of transverse 

 |^ veinlets beginning before half-way. 7. 



f M remains unbranched except at its distal end. 



J Scytinoptera HandL 



*• ' 1 (Upper Permian of Kama River, Russia). 



M branching into two at or before middle of wing. 6. 



(2) 



