In a paper communicated to the 'Entomologist' in February, 1889,[[52]] by Mr. W. W. Smith, the author makes some interesting remarks on the variation of this butterfly, as observed by him in Canterbury and Otago. After pointing out the great diversity exhibited by different specimens in the depth of colouring, and in the number and size of the ocelli, he states that in his opinion the greatest variation occurs during the summers that succeed wet winters. In the year 1888 I had the opportunity of inspecting a most interesting series of this insect, presented by Mr. Smith to the Wellington Museum. They embraced specimens of very varied colouring, and included, amongst other remarkable forms, a male, which was entirely destitute of all ocelli, both on the fore- and on the hind-wings. Amongst these specimens, however, I did not see any resembling those I have described from Nelson and Marlborough. This collection has, I regret to say, since been disposed of by the Museum authorities, and cannot therefore be utilised by New Zealand students.
The larva of this insect feeds on the tussock grass (Poa australis). Its length, when full grown, is about 1 inch. The top of the head is furnished with a very large process, which projects forwards. The body is much attenuated towards the tail, which is bifid. The general colour is dull green, with a crimson line on each side and numerous alternate lines of yellow and white. The legs and prolegs are very small. There are four wrinkles on the posterior edges of each segment.
When feeding, this caterpillar rests on a blade of the tussock, where it is very inconspicuous. It appears to prefer the dead or drier portions of the grass, and feeds and grows very slowly. It is strictly diurnal in its habits, relapsing into a death-like repose at night.
The pupa is suspended by the tail to an upright blade of the tussock. In the specimen I reared, I was fortunate enough to witness the actual transformation, and during the process, observed it seizing hold of the larval skin with its posterior segments, its manœuvres whilst thus engaged exactly resembling those of the pupa of Anosia erippus, described above by Professor Riley.
The length of the pupa is about ½ inch. Its colour is bright green, with a reddish line along the edge of each wing-case, and several white lines on the sides and back.
The perfect insect appears from December till the end of March. It is usually very abundant where found, the males being more numerous than the females in the proportion of about five to one. It flies amongst the tussock grass in a weak and aimless manner. When rapidly pursued it has a habit of plunging into a tussock and closing its wings, where it remains quite invisible until the danger is past.
The silver stripes on the under side of the hind-wings are very protective to the insect when at rest on its food-plant, the striped coloration of the larva and pupa no doubt serving similar protective purposes.
Genus 2.—DODONIDIA, Butl.
Characters as in Argyrophenga, except that vein 11 of the fore-wings rises from upper margin of cell, shortly before transverse vein.
We have one species in New Zealand.