Art. XVIII.—Description of a Species of Butterfly new to New Zealand and probably to Science.
[Read before the Philosophical Institute of Canterbury, 30th November, 1882.]
Family NymphaldÆ, Westwood.
Genus (?)—helmsi, n. sp.
Male.—Head small; eyes naked, large and prominent; antennæ scarcely more than a third of the length of the costa of the forewing; shaft slender, club small, flattened, rather elongate, and slightly curved, but not hooked; tip of the club fulvous; palpi long obliquely ascending, a little wider apart at the tip than at the base, thickly clothed with long bristly hairs, terminal joint small and pointed, the hairs on the upper and lower edges and tip black, on the sides (both inwardly and outwardly) white; forelegs rudimental, rather slender, scantily clothed with long slender hairs; hindlegs with a pair of small spurs at extremity of the tibiæ; tarsi with two simple claws.
Primaries broad; costa convex from the middle to the tip; hindmargin nearly straight, slightly tending to concave; the costal and median nervures dilated at the base. Upper side of primaries dark-brown, a transverse fulvous band, extending in a slight curve from the subcostal to near the submedian nervure and thence bending towards and terminating about two
lines from the anal angle, the inner margin of this band crossing the median nervure at the point from which the third median nervule springs, and the outer margin at the point from which the second median nervule springs, a transverse fulvous band beyond the discoidal cell, and extending from the costa to the anal angle, and bent outwardly at the first median nervule and gradually attenuated thence to the posterior angle; another and narrower fulvous band extending from the costa midway between the apex and the last described band, and joining the latter below the subapical ocellus round which it bends and by which it is nearly severed; a subapical white-pupilled black ocellus on a dark ground: under side of primaries similar to the upper, especially the brown of the basal third and the fulvous bands near the costa, the inner and middle bands being confluent at the inner margin; the interior band from the ocellus to the costa silvered, also the middle band silvered on the costa, and a very narrow submarginal silver band from the costa to near the third median nervule.
Secondaries.—Discoidal cell closed; anal angle elongated (possibly caudate, but the anal angle of both hind wings is too much chipped to determine with certainty). Upper side of secondaries dark-brown; a submarginal fulvous band extending from the first subcostal nervule to the third median nervule; another fulvous band extending from the middle of the costa, and running into the submarginal band below a white-pupilled black ocellus which nearly severs the middle band—the latter ocellus situated in the space between the lower discoidal and the first median nervules, and above it a similar but less distinct ocellus, and above that an indication of another but obsolete ocellus—the three ocelli connected and occupying the space between the fulvous bands; a similar ocellus on the anal end of the submarginal band between the second and third medial nervules. Under side of secondaries brown but paler than the upper; the bands of the upper side indicated below by silver bands, but the inner completely severed from the outer by the lower of the three connected ocelli which are repeated as on the upper side, but each surrounded by a narrow pale brown ring, and the iris and pupil of each fully developed; the ocellus near the anal angle repeated as on the upper side, but surrounded by a broad fulvous ring; a very narrow submarginal silver band running from the anterior angle to the anal ocellus; a silver stripe along three-fourths of the inner margin from the base; a silver band extending from the costa near the base to near the anal ocellus, broad at the costa and attenuated to a point near the ocellus; and, between the latter band and the stripe on the inner margin, another narrow silver stripe.
Expanse of wings, 1″ 10″′.
Hab. Paporoa Range, near Greymouth.
I have described this butterfly from a single specimen submitted to me by Mr. J. D. Enys for description. He informs me that it was captured by Mr. R. Helms, of Greymouth, at an altitude of about 1,200 to 1,500 feet above the sea. Unfortunately the specimen is chipped and frayed at the anal angle of the hindwings, so that the caudate form of that angle cannot be exactly defined.
The genus of the insect I do not venture to determine, not having access to the descriptions of the various genera of the family to which it belongs.
There appears to be much confusion in the definition of the neuration of the wings of Lepidopterous insects—especially with reference to the notation of the nervules, or branches of the nervures, which are indicated by numbers—in consequence of some entomologists counting in a direction from the costa towards the inner margin, and others in the opposite direction. I have therefore thought it desirable to state that in the above description I have adopted the former notation, that is counting from the costa towards the hind margin, a notation which accords with that indicated in the diagram of “Terminology of the wings of Papilioniœ“given in “Catalogue of Lepidopterous Insects in collection of the British Museum, part 1, Papilionidæ, 1852.“
I take the present opportunity of calling attention to the very incorrect reprint, in Mr. J. D. Enys' Catalogue of the Butterflies of New Zealand, 1880, of my diagram illustrating the difference of neuration in the wings of Erebia blandina, Percnodaimon pluto, and Erebiola butleri. The inaccuracy renders the diagram worse than useless, inasmuch as the object of my diagram was to show the position of the nervures and nervules, and in the diagram in Mr. Enys' Catalogue they are wrongly placed. Great care should always be taken in printing diagrams of this character.