Art. XIX.—A few Notes on the Economy and Habits of one of our largest and handsomest New Zealand Butterflies (Pyrameis gonerilla).

Transactions and Proceedings of the Royal Society of New Zealand, Volume 21, 1888, Page 196

Art. XIX.—A few Notes on the Economy and Habits of one of our largest and handsomest New Zealand Butterflies (Pyrameis gonerilla). By W.Colenso, F.R.S., F.L.S., &c. [Read before the Hawke's Bay Philosophical Institute, 8th October, 1888.] A Few years ago, during my visits to our inland forests, I often had to pass close to a large shrubby Urtica,* U. ferox, Forst., or a closely allied and undescribed species: U. pungens, MSS. and I invariably saw several of our large and handsome butterfly, Pyrameis gonerilla, hovering over it or settled on it. The shrub itself was in a sheltered sunny nook; and on one day in particular in early spring I counted no less than seventeen of these beautiful creatures at one time so engaged about that shrub, which none of them seemed desirous of leaving. It was a truly lovely scene which I well remember. Spring's woodland harbinger, the large-flowered clematis (C. indivisa) was pretty well-developed overhead, swinging and displaying its long wreaths of peerless and pendulous virgin-white tresses from the lofty trees up which it had climbed when young; around were the many beautiful and stately tree-ferns, while below the ground was thickly carpeted with that neat close-growing bedding plant, with small and regularly - formed emerald foliage, Pratia angulata, expanding thankfully its myriads of white and blue star-like blossoms to the morning sun, and so drinking in life. The sun, too, was shining brightly down from the deep concave of the dark-blue sky, rarely flecked by a passing cloud; while the melodious tuis (Prosthemadera novæ-zealandiæ—parson-bird of the colonists), having had their breakfast of honey and nectar, were singing away joyfully and with good courage from their tiptop perches on the highest sprays, their dark and lustrous metallic plumage reflecting the rays of the sun. It is worthy of notice that this handsome and highly melodious bird always selects the highest and bare spray of a tall tree for its music-stool,

whence to pour forth its gushing notes; and this habit is more particularly observed by them soon after sunrise and at sunset, when to hear them of a fine summer's evening, when all is calm above and still below, is really ravishing. At such times the song by Capern, called “The Old Grey Thrush,” has come forcibly to mind. As some of you may not know it, permit me to give part of the first stanza:— Of all the birds of tuneful note That warble o'er field and flood, O, give me the thrush with the speckled throat, The king of the singing wood! For see, he sits on the topmost twig To carol forth his glee, And none can dance a merrier jig, Or laugh more loud than he. The whole of that song is apt (for the tui), and well worth repeating. To return, however:—altogether it was a pleasant time; all nature seemed in harmony; even the murmur of the rippling waters of the neighbouring brawling stream joined in unison, and conveyed a more soothing cadence than usual to the ear; and the briskly flitting butterflies above all appeared to be revelling in luxury, enjoying themselves and making the most of it. At such seasons snatches from the once popular song of fifty or sixty years ago, and long forgotten, “I'd be a butterfly, born in a bower,” &c., would come rushing rapidly along through the dark lanes of encumbered memory into broad daylight. I remember well, standing entranced, as it were, for several minutes, contemplating and admiring the scene before me ere I could bring myself to resume my journey, and dive into the deeper and gloomy recesses of the forest. That is a faint and brief description of what I saw there at that grand butterflies' ball and feast, in the early spring. On a subsequent visit to that spot, one day in the autumn (28th April), on examining the Urtica shrub, I found 3 larvæ and 2 chrysalides of the Pyrameis on it: the larvæ feeding on its leaves, the pupæ hanging from it. The pupæ were suspended by a few tiny threads under a leaf, or within a leaf (or sometimes two leaves), the edges being very slightly drawn together with threads, but not closed up, remaining more than half open. In taking these rudimental insects, and gathering some of the leaves of the Urtica for the larvæ to feed on, I somehow got stung rather severely, in spite of all my care. I well remember the sharp permanent pain from the sting of that nettle, which lasted four days,* Since writing the above I find the same fact already recorded—“Fl. N.Z.,” vol. i., p. 225, and “Handbook Fl. N.Z.,” p. 252—I having forty years before experienced the same discomfort. and was always increased through washing or wetting my hands.

Four days after I again visited that spot and Urtica shrub for the last time that season (as I was to return to Napier the next day), and found 3 more larvæ and 2 chrysalides, and brought them all away. Arriving at Napier on the 2nd May, I placed the larvæ, with a quantity of fresh leaves, in a large white glass bottle; on the 4th, one of the larvæ had suspended itself to the (bored) cork of the bottle; on the 6th it cast its larva-skin and partly took up the chrysalis appearance, but was very wet at first; and on the 7th it assumed the true chrysalis aspect. On the 9th another of the larvæ hung itself to the cork, head downwards, and commenced its transformation. On the 11th one of the chrysalides dropped off from the cork; I had noticed that this one was smaller and of a lighter colour. On the 18th another of the larvæ entered into its chrysalis state, also attaching itself to the cork of the bottle. On the 19th one of the chrysalides I had brought in that state from the forest burst, and the perfect insect emerged; but, owing to the shallowness of the glass in which these forest chrysalides were confined, one wing had got stuck fast to the side of the bottle in the process of emerging, and so became contracted and rigid when dry, like a little plaited epaulette; while the other wing, being free, had attained to its full size and shape; but the poor creature was sadly lopsided. On the 21st another of the forest chrysalides split open, and the imago emerged—a beautiful sight,* See the full description of similar emergence of Danais berenice, as witnessed by me (“Trans. N.Z. Inst.,” vol. x., p. 279). once seen, never to be forgotten. A thing of beauty is a joy for ever. This was a fine and perfect specimen of this butterfly. I regretted much those larvæ that entered into their pupa state here in Napier not emerging therefrom as perfect insects. I suspect this was owing either to their not having been fully fed down to the time of their entering into that state, or that they assumed it too early, and perhaps in an unhealthy state. As larvæ they were very voracious; it seemed as if they were always eating, night and day; so that my stock of Urtica leaves that had cost me so dearly were soon disposed of. On their being used up I tried the hungry creatures with several other leaves of Maori plants, but none would they touch. That shrub itself, though a large bushy and spreading one (about 5ft. high and several feet round), with several others, smaller ones, close by, almost always presented a sorry sight from their leaves being so gnawed and stripped; hence I had always some difficulty in procuring good specimens of it for drying and preserving. Those Urtica plants, however, recovered themselves throughout the winter, and were fully

foliaged in early spring. I may also mention that, though the plant was said to be well known in that locality, I only met with it in one other spot, and that a single small specimen. Seeing that the larvæ in their purely natural state always either suspend themselves to a twig or enwrap themselves in a leaf of the Urtica, it seemed strange that in no case did one of them so suspend itself to a stem in the bottle, but only and always to the cork (of course there were no leaves left). Was this done on account of more moving air there through the holes—such being requisite to dry their wings quickly when emerging—or to be in a position of more free space? As I suppose both larva and pupa of this butterfly to be, like the perfect insect, well known, I do not attempt to describe them. The larva is a curious-looking object, from its being so very hairy; the hairs, too, are rather long, rigid, patent, dark-coloured, and produced in little bunches of irregular lengths. Notwithstanding my partial failure in the rearing of them, a few plain facts in the natural economy of this butterfly seem to be substantiated: (1) That its larvæ feed on the leaves of Urtica ?pungens, Col., and are very voracious; (2) that on their entering into the chrysalis state they wrap themselves loosely in a leaf of the same plant, to which they are also fastened, or suspend beneath a leaf from its petiole or branchlet; (3) that the time occupied by the embryo insect in its chrysalis state is more than three weeks; (4) and that if it has not ample room for unfolding its wings on emerging from the chrysalis state they become stunted and useless, and then of course the insect is destitute of flight. Addendum. I may here mention a similar case, as to contraction of wings under similar circumstances, that occurred a few years ago. In 1884, in a case of apples received from America (? California), I found a fine butterfly; one quite as large as our New Zealand Pyrameis gonerilla, if not much larger. It was but recently dead, and had evidently died in the case during the voyage; both of its wings were much crumpled and contracted, and its back chafed. Its prevailing colours were yellow and black (bluish-black) in broad streaks, the body the same, with broad yellow longitudinal stripes; very hairy at edges of wings in some parts; hairs long, yellow; and two large red spots on the wings; antennæ very dark, slender, naked; tips slightly clubbed; eyes very large and prominent. Being much crumpled, an only specimen, and tender, I only give its more striking aspect, as it requires to be softened and carefully laid out, before a strictly accurate description could be given. It is wholly unknown to me.