First Inter-anal Cross-vein (ia1).—All the species have this cross-vein, except demissa, barbarica, rosicoma, and zonodoxa. Its absence is accompanied by a weakening of the anal veins. Anal Veins (1A, 2A, and 3A).—The arrangement of the anal veins is very peculiar, and varies little throughout the genus. At about two-thirds of its length 2A curves sharply upwards and joins 1A, 3A following a similar course in relation to 2A. In one species, however, ianthina (fig. 9), 2A does not join 1A or curve towards it. In calliarcha (fig. 10) 2A bends towards 1A at ia, and from thence sharply downwards again, thus giving an unusual appearance to what is essentially the same structure. In some of the species the anal veins are very weakly chitinized, and can only be traced with difficulty. The Hindwing. Subcostal Vein (Sc).—Sc forks into Sc1 and Sc2 in all of the species. In a few of the forms an interesting feature is present in connection with the stalk of the vein. In doroxena this appears to consist of two veins lying closely alongside each other, but not fused, the condition being observable from the normal forking to near the base—that is, for at least four-fifths of the stalk. In calliarcha the division can be traced nearly to rf, and the vein is of double width for some distance basad of this. In lucilia the double nature of the vein is obscure near the normal forking, but becomes more pronounced farther basad, while in ianthina the division is apparent for about one-third of the apical portion. The basal dichotomy of Sc is not known in any living insect, but Tillyard has shown (Proc. Linn. Soc. N.S.W., vol. 44, p. 548, 1919) that in the fossil Archipanorpa (order Protomecoptera), though the basal part of the wing is missing, the apical portions of Sc are in such a position as to point to a junction far basad, while in Aristopsyche (order Paratrichoptera) the actual basal fork is observable. It is not, however, claimed that in this apparent double vein in the foregoing species we have an indication of the persistence of so remote an ancestral character as the basal forking of the subcostal vein. Dr. Tillyard, who has seen my preparations, suggests the following explanation: “The double formation is a specialization of the imaginal venation following upon an exceptionally strong splitting-back of the precedent subcostal trachea in the pupal wing. It is well known that in the order Lepidoptera the wing-tracheae tend to split back into separate tracheae running alongside one another to points far basad from the normal points of forking of the vein. If two such tracheae became slightly more separated, the superimposed chitinization at metamorphosis would produce a double vein in the imago. This seems to be what has actually happened in the case here under discussion.” Radius (R).—As R1 has been fully dealt with in the earlier part of the paper, the details need not be repeated here. The radial sector is twice dichotomically forked as in the forewing, but there is greater variation in the length of the stalk, particularly in regard to R4 and R5. In doroxena (fig. 11) R4 and R5 are connate; in aurella and ianthina they are short-stalked; in barbarica, quadrijuga, incongruella, eodora, and zonodoxa the forking is from about half-way; while in rosicoma, lucilia, calliarcha, chrysargyra, demissa (fig. 12), and caustica the stalk is long. R2 and R3 are more uniform in the length of stalk, but in the only specimen of caustica examined R3 was absent; quite possibly, however, this was merely an individual variation.