2 
Pee ae Pateh OP RENE es eR Be ROPES ek me 
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Structure of some Australian Lepidoplera Homoneura. 595 
of a group of strong hairs assisting in this articulation; 
I propose to call these the prejugal bristles (p.7.). In 
the fore-wing the humeral crossbar from the subcostal 
near its base to the costal margin, present in some species 
of Sabatinca, is not developed; the subcostal branches 
into Scl and Sc2, the first radial into Rla and R1b; the 
radial sector divides dichotomously; R5 runs to the 
apex of the wing; an inter-radial crossbar (7. 7.) is present, 
completing the areole, which, as I have elsewhere insisted, 
is a primitive structure in the Lepidoptera. That the 
absence of a median cell is due to the absence of the inter- 
median crossbar consecutive to a distal position of the 
bifurcation of M1 and M2, is, I think, proved by Tillyard’s 
figure (B., p. 106) of the pupal tracheation of the fore- 
wing of Eriocrania. It is a specialised form of reduction 
not, I think, found elsewhere among the Lepidoptera. 
The Hepialidae (Fig. 8) and several families of the Hetero- 
neura like the Cossidae have in this instance preserved a. 
more primitive structure. The media has three developed 
veins, together with a fourth (M4), which joins the cubitus 
at its bifurcation into Cula (really a conjoint vein 
Cula + M4) and Culb. Comstock (p. 314) regards this as 
a medio-cubital crossbar homologous with that found in 
the Trichoptera; but if the Micropterygidae are really 
lepidopterous, as I believe, it must be homologous with 
M4 as it occurs in the Hepialidae and Heteroneura. The 
basal connection of the media and cubitus by the posterior 
arculus, which Tillyard (B., p. 637) suggests may be a 
fifth branch of the media (M5), is very clearly developed. 
This is a primitive structure of which very little, if any, 
vestige remains in other groups of Lepidoptera in the 
neuration of the imago. . The second branch of the cubitus 
is seen arising directly from its main stem. Unfortunately 
by most authors, including Comstock (J. c.), this branch 
together with the main cubital stem have been mistaken 
for the first anal. The first and second anals are repre- 
sented by a short loop at the base of a conjoint vein. 
The third anal I have not been able to distinguish. 
The neuration of the hind-wing is very similar to that 
of the fore-wing with some not unimportant differences 
due to reduction. The subcostal is branched, but Rl 
appears to be so completely absent that no trace remains 
to show what has become of it. The clue to its mode of 
disappearance is shown in a denuded example of Sabatinca 
