Genus 1.—CHRYSOPHANUS, Hb.

"An extensive and nearly cosmopolitan genus. Larva short, stout, attenuated at extremities, with short hairs. Pupa attached by the tail and central belt of silk, or sometimes unattached on the ground."—(Meyrick.)

There are three New Zealand species.

CHRYSOPHANUS SALUSTIUS, Fabr.

(Plate XII., fig. 18 ?, 19 ?, 20 and 21 under side; Plate XIII., figs. 2, 3, 4, and 5 varieties.)

This pretty little butterfly appears to be very common in most parts of New Zealand. I have records of its occurrence in abundance at various localities, from Napier southwards to Invercargill.

From the foregoing it may be seen that the variation in this insect is considerable. After a careful examination of a large number of specimens taken at various localities in both North and South Islands, I am, however, unable to find characters of sufficient constancy to entitle any of the forms to specific rank. The most striking of these varieties appears to be that described by Mr. Bates as Chrysophanus feredayi.^[55] (See Plate XIII., fig. 2, upper side; Plate XII., fig. 21, under side.) On the upper surface it has the central series of spots almost forming a band in the male, and the coppery ground colour is paler than in the typical form. On the under side the borders of the fore-wings, and the whole of the hind-wings are dull brown. This form closely resembles C. rauparaha, Fereday.^[56] C. maui, Fereday, is evidently that variety of the male having the veins bordered with two fine black lines. Mr. Fereday states that he has never been able to find the female of his C. maui. This is readily accounted for by the fact, that the female of C. maui is nothing more than the female of C. salustius.

Recently two very remarkable aberrations of C. salustius have come under my notice; one captured by Mr. Hawthorne at Karori, in which the hind-wings are almost entirely suffused with blackish-brown, excepting a small patch of copper colour near the centre, and two patches on the termen. Another specimen, taken by Mr. Grapes near Paraparaumu, has the fore-wings also suffused with blackish-brown, except near the middle, where there are five coppery patches between the veins. On the under side there are six large oblong spots near the termen of the fore-wings, and a series of dusky oblong spots on the hind-wings. (See Plate XIII., fig. 3, fig. 4 under side.) Plate XIII., fig. 5, represents another variety discovered by Mr. Grapes on the coast near Paikakariki, in the Wellington district. It is remarkable for the bright blue terminal spots which are present in both sexes.

The eggs of C. salustius, when first deposited, are pale green with yellow reticulations, the whole egg having a honeycombed appearance when magnified. They become uniform pale yellow before hatching. The young larva is shaped somewhat like a wood-louse. The head is quite hidden by the three anterior segments, which are much larger than the rest. After the first moult the larva becomes bright green, with a crimson line down the back; the head is then larger, and the three anterior segments considerably reduced. Unfortunately the life-history could not be investigated beyond this point, as the larvÆ all died. The time of year when this occurred was late autumn, and it therefore seems probable that the larvÆ hibernate and undergo their transformation early the following spring.

The perfect insect first appears in November and continues abundant until the middle or end of February. Specimens of what I believe to be a second brood may be taken in March and April if the weather be fine, but in stormy seasons these are frequently not observed. I have also noticed that the autumnal specimens are usually smaller and paler in colour than those captured in the spring.

This butterfly frequents open situations, and in fine, sunny weather it is often very common.

CHRYSOPHANUS ENYSII, Butl.

(Chrysophanus enysii, Butler, Ent. Mo. Mag. xiii. 153 (1876).)

(Plate XII., fig. 22 ?, 23 ?, 24 under side.)

This species is tolerably common in the Wellington district, and I expect it will be found to occur in most localities in the North Island. I have also taken the insect at Nelson, but have not heard of its capture elsewhere in the South Island.

This insect varies chiefly in the extent of the dark markings on the upper side, which sometimes very much encroach on the golden ground colour. The spaces between veins 2, 3, and 4, near their origin are sometimes yellow and sometimes black, but, as every intermediate form exists, cannot be distinguished as species. Mr. Fereday regards the form with the black spaces as C. feredayi, Bates. As previously stated, however, I am inclined to think that C. feredayi, Bates, is the same form as C. rauparaha, Fereday.

This butterfly is essentially a forest-loving species, and may sometimes be taken quite plentifully in sunny openings on fine days, during December and January. It is not nearly so common as C. salustius, and I do not think that there is more than a single brood in a season.

CHRYSOPHANUS BOLDENARUM, White.

(Plate XII., figs. 13, 14, ? varieties, 15 under side of ?, 16 ?, 17 under side of ?.)

This brilliant little butterfly is very common in most localities in the South Island. In the North Island it has occurred at Lakes Wairarapa and Taupo.

This insect is extremely variable, but I do not think it likely that any of the numerous forms will prove sufficiently constant to be regarded as distinct species. The male varies in the size and number of the black spots, many of which are often absent; in the extent of the purple sheen which is sometimes absent from the hind-wings, sometimes partially absent from the fore-wings, and sometimes extends over the whole of both pairs of wings; also in the colour of such sheen, which often inclines towards blue. Some specimens are much paler than others, and so far as my experience goes, these are chiefly found at considerable elevations; in such specimens, the ground colouring inclines towards yellow or orange, and the purple sheen is very brilliant, and extends over the whole of the wings. The female of this form is proportionately paler. Other specimens have the hind-wings almost black with no purple sheen, whilst in others the purple sheen remains. Another form has the usual markings, but the hind-wings are deep orange-brown, without purple sheen, which is also absent from the outer portions of the fore-wings. One female in my collection is dull brown, with yellow markings between the two rows of black spots. The under side is still more variable. One very striking form has only the basal portions of the fore-wings yellow, the rest of the ground colour is pale bluish-grey, and the spots black. On the hind-wings there are a number of black spots near the base; then an irregular band of black, and then a double row of marginal spots. An almost unlimited number of varieties appears to connect this form with one, in which all the markings on the hind-wings are nearly obsolete. The specimens of this insect taken in each district appear to exhibit differences from those taken elsewhere, but specimens also differ from the same district, so that at present we are unable to detect any well-marked local variation, or topomorphism, as it has been termed. It is consequently highly desirable that collectors should endeavour to obtain specimens from as many localities as possible, so that the nature of the variation of this butterfly may be better understood.

Mr. Fereday states^[57] that after carefully examining a patch of Donatia novÆzealandiÆ, a plant he had noticed much frequented by this butterfly, he succeeded in finding a larva which there could be little doubt would have given rise to this insect, had it lived. The following is taken from his description: The caterpillar is shaped like a wood-louse, hairy, and pale green. There is a series of conical purplish spots down the back, edged first with white, and then with dull red. On the sides there is a series of pale pinkish oblique stripes, blended with dull red towards the spiracles.

The perfect insect is very common in dry, stony places, generally near river-beds, during January, February and March. It flies only a short distance when disturbed, but is very quick on the wing, and hence difficult to catch until one becomes accustomed to it. In some places these little butterflies are so abundant that they take wing like a swarm of blow-flies. They seldom open their wings whilst at rest, so that when perched on the ground they are very inconspicuous.