BY R. J. TILLYARD. 425 



G. heterogena. Though the two species of Karschia are of smaller 

 size than the true species of Gynacantha, yet G. heterogena again 

 is smaller still. And though Karschia exhibits several important 

 differences from the true species of Gynacantha, yet G. heterogena 

 (female) again exhibits important differences from Karschia. 

 Hence I will not attempt to rope in the females of Karschia with 

 heterogena, whilst, on the other hand, it is impossible to ignore 

 the striking characters of the male of heterogena and attempt to 

 place it, by female characters only, under the genus Karschia. 



I propose to found a new genus Austrogynacantha for the 

 reception of the beautiful and remarkable species Gynacantha 

 heterogena. 



Austrogynacantha, n.g. 



Type Gynacantha heterogena. 



Characters as in Gynacantha Rambur, viz., "Face narrow, eyes 

 large, touching for a long space, slightly sinuous behind, occiput 

 very small. Second segment of abdomen in male having a pro- 

 nounced tubercle. Appendages of male simple, slender; last 

 segment in female jutting out and prolonged below, furnished 

 with long spines [two or three only in the species which I know]; 

 membranule nearly nil,"* but with the following important 

 exceptions and differences, shown best by a comparative 

 enumeration. 



Gynacantha (s.str.)[6r. Eosenberghif Selys]. — (1) Large insects, 

 expanse of wings in $ 90 mm. at least. (2) Abdomen of both 

 sexes sharply constricted at segment 3. (3) Spurs of segment 2 in 

 <J very conspicuous, rounded. (4) Hindwings very broad. (5) 

 Anal margin of hindwing of £ strongly angulated; the outer side 

 of the anal triangle composed of a very strong and thick vein, 

 much stouter than the continuation of the postcostal margin; 

 anal angle conspicuously angulated. (6) Anal triangle of hind- 



* Eambur, Neuropteres, p.209, 1842. 

 t I have chosen this species as being one that is both well known to me 

 and very typical of the genus. 



