416 STUDIES IN AUSTRALIAN NEUROPTERA, viii., 



I propose to continue to treat them as a separate Order for the 

 present. This point of view, I may now say, has been justified 

 by the discovery that the larva of Ithone does actually possess 

 the typical suctorial jaws of the Planipennia, although its pupa 

 lies free in the earth, without a cocoon. 



If, then, we are agreed that the Ithonidw are an archaic group 

 of insects, deserving of family rank within the Order Planipennia, 

 we have next to enquire into the composition of that family. 

 Comstock (1, p. 177) "has recently suggested the inclusion in it 

 provisionally of the remarkable Oriental genus Rapisma. I agree 

 with Comstock that "the limits and distinguishing characteristics 

 of the Ithonidce must be determined by a study of other char- 

 acters as well as those presented by the wings"; but, until this 

 can be done for Rapisma as well as for Ithone, I cannot accept 

 the inclusion of that genus within the family. Hence I propose 

 to omit it from consideration in this paper, and to confine my 

 attention to the purely Australian insects belonging to the genus 

 Ithone and its close allies. 



We are now faced with an initial difficulty as to the identity 

 of Newman's original type of Ithone fusca. In 1853(7), Newman 

 wrote: — "The Ithonesidce appear to be a numerous group, con- 

 fined to New Holland. Ithone is the only genus described, but 

 there are many species, and these very dissimilar, and likely to 

 be generically subdivided when we become better acquainted 

 with the entomological productions of the wonderful country in 

 which they are found." Thus he must have known of the exist- 

 ence of other species besides his /. fusca at this date, though he 

 did not describe any, and did not attempt to indicate more fully 

 the distinguishing characteristics of the single species he had 

 described. The next species described was Varnia perloides 

 Walker, from Western Australia, in 1860. The types of this 

 insect and of I. fusca are both in the British Museum. The only 

 other Ithonidce so far described are Nespra implexa Navas, from 

 Central Australia, in 1914, and Ithone fulva Tillyard, from 

 Queensland, in 1916. The type of the former is in the British 

 Museum, that of the latter in my collection. 



