38 
Psyche 
[March 
venation, for although there are fully twice as many term- 
inal branches in the ithonids as in Oliarces, such diversity 
likewise occurs within the Hemerobiidae. 
The general body structure of Oliarces , including the 
small, retracted head, and the large abdomen, strongly re- 
sembles that of the ithonids. The terminal abdominal seg- 
ments, however, present some interesting differences. In 
the male of Ithone, as well as of Heterithone and Varnia , 
the ninth abdominal tergite is entire dorsally, even though 
much constricted (Plate 4, fig. 1A). The ninth sternite 
(hypandrium of Tillyard’s terminology) of these genera, as 
in nearly all Planipennia, is extended further posteriorly 
than the tergite, but it is not nearly so modified here as in 
most Neuroptera. The tenth tergite, which includes the trich- 
obothria, bears a pair of conspicuous anal plates, extend- 
ing posteriorly and slightly curved inwardly. The tenth 
sternite is apparently reduced to internal plates, as in nearly 
all other Neuroptera. The homologues of the sclerites are 
Text-fig. 3. A, Terminal abdominal segments of female of Ithone fusca 
Newman. Drawn fiom specimen in M. C. Z. (Woy Woy, N. S. W., 
Nov. 3, 1918, R. J. T.). Lettering as in text-figure 1. B, Terminal ab- 
dominal segments of female of Oliarces clara Banks. Drawn from allo- 
type. Lettering as in text-figure 1. 
readily found in Oliarces. Its ninth tergite is more con- 
stricted medially than in Ithone , but it is still undivided. 
The ninth sternite has migrated further posteriorly, and 
is smaller than in Ithone, but is otherwise similar. The anal 
plates of the tenth tergite, though directed upwards instead 
