The larva feeds on Todea hymenophylloides, a fern which grows in shady places in the depths of the forest. The length of the caterpillar when full grown is about 1¼ inches. It is very variable; some specimens are dull brown, with a row of green or pale brown lunate spots down each side, and a dark brown line down the back. Others are bright green, with a diagonal reddish-brown stripe on the side of each segment; the segmental divisions are reddish-brown, intersected by numerous very minute whitish lines.
The pupa is enclosed in a loose cocoon on the surface of the ground.
The perfect insect appears from November till March, and is very common in forest regions. It may often be dislodged from the dead fronds surrounding the stems of tree-ferns, and is also met with in great abundance towards the end of summer on the blossoms of the white rata.
Genus 4.—SESTRA, Walk.
"Face smooth. Palpi short, rough-haired beneath, porrected. Antennæ in male stout, serrate, shortly ciliated. Fore-wings with vein 6 from below 9, 7 from below angle of areole, 10 rising out of 9 above origin, anastomosing again shortly with 9, 11 anastomosing shortly with 10, 12 anastomosing shortly with 11. Hind-wings normal."—(Meyrick.) (Plate [II]., fig. 53, neuration of fore-wing of Sestra humeraria.)
We have two species in New Zealand.
It will be seen that my figure of the neuration of Sestra humeraria does not precisely agree with Mr. Meyrick's description. The differences in the results arrived at are probably due to the variability in structure of veins 10, 11 (and 12), mentioned when dealing with the characters of the entire family. Similar slight discrepancies also occur in connection with the three following genera.
SESTRA HUMERARIA, Walk.
(Macaria humeraria, Walk. 940. Lozogramma obtusaria, ib. 985. Cidaria obtruncata, ib. 1421. Sestra fusiplagiata, ib. 1751. Amastris encausta, Meyr., Trans. N. Z. Inst. xvi. 105. Sestra humeraria, ib. xviii. 184.)
(Plate [X]., figs. 1 and 2 varieties; Plate [III]., fig. 20, larva.)