  "Characters of NymphalidÆ, but fore-wings with vein 12 greatly dilated towards base." (Plate I., figs. 25, 26, and 27, neuration of Erebia pluto.) "A large group of very general distribution. The species are usually of moderate size, generally dark coloured with light bands or spots, and with several round, black, white-centred spots on lower surface. Some of them are more fond of shady places than is customary in this group. "Ovum spherical-ovate, surface reticulated and often ribbed. Larva more or less tapering towards extremities, with short hairs; segment 13 ending in two points; feeding on grass. Pupa suspended by the tail or unattached, sometimes subterranean."—(Meyrick.) (See Plate III., figs. 4 and 5 larvÆ, 28 and 29 pupÆ.) Of this family we have three genera represented in New Zealand:— 1. Argyrophenga.2. Dodonidia.3. Erebia. Genus 1.—ARGYROPHENGA.Eyes glabrous. Club of antennÆ somewhat abrupt. Fore-wings with lower margin of cell greatly dilated towards base; veins 8, 9, 10, and 11 out of 7; vein 12 greatly dilated towards base. Of this genus there is one species in New Zealand. ARGYROPHENGA ANTIPODUM, Doubleday. (Argyrophenga antipodum, Doubleday, Ann. and Mag. Nat. Hist. xvi. p. 307 (1845); Gen. Diurn. Lepid. pl. 63, fig. 6 (1851); Butler, Erebus and Terror Lep., pl. 8, figs. 4, 7 (1874).) (Plate XI., fig. 4 ?, 5 ?, 3 variety, 6 under side of ?, 7 under side of variety; Plate III., fig. 4 larva, fig. 29 pupa.) This species occurs commonly on the tussock lands from Christchurch to Invercargill. In the provinces of Nelson and Marlborough it is, I believe, confined to situations having elevations of from 2,000 to 4,000 feet above the sea-level. It has never been captured in the North Island. The expansion of the wings varies from 1? to 1¾ inches. Above, all the wings are dull brownish-black, paler near the body; the outer portion of each is covered with a large patch of bright orange-brown (northern form), or fawn colour (southern form); on the fore-wings this patch contains a large oval black spot, with two white dots in the middle; on the hind-wings there are two, three, or four black spots, with one white dot in the centre of each; beneath, the markings on the fore-wings resemble those of the upper surface, except that there are often several short silvery stripes near the apex; the hind-wings are dull yellow, with silver streaks between the veins, and one broader streak in the centre of the wing. The female is much paler than the male, with the borders of the wings whitish. This insect is extremely variable. The colouring appears to be much influenced by local conditions. On the Dun Mountain, Nelson district, at an elevation of about 2,700 feet, a very small light form occurs in which the sexes are almost exactly alike. There are only two perfect spots on the upper surface of the hind-wings; the other spot is Besides these extreme variations, which appear to be largely dependent on local conditions, great variability exists with respect to the number and size of the ocelli or white-centred spots. In some specimens there are no ocelli on the hind-wings; in others, two, three, or four very minute ones, whilst others have all four very large. Occasionally specimens have a minute ocellus below the large one on the fore-wings. Were it not for the intermediate varieties, there would probably be little hesitation in separating the extreme forms of this insect into several distinct species; but as they are connected by a host of intermediate forms, it is quite impossible even to divide them into varieties. 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 manoeuvres 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. DODONIDIA HELMSI, Fereday. (Dodonidia helmsi, Fereday, Trans. N. Z. Inst. xv. 193.) (Plate XI., fig. 14, fig. 15 under side; Plate III., fig. 5 larva, fig. 28 pupa.) A single specimen of this interesting butterfly was discovered by Mr. R. Helms, in 1881, on the Paparoa Range, near Greymouth, at an elevation of about 1,500 feet above the sea-level. Until within the last three years only three other specimens had been captured, viz., one near Wainui-o-mata, in Mr. A. P. Buller's collection; one on the Dun Mountain, Nelson, at an elevation of about 2,500 feet, which is in my collection; and one on the Tableland of Mount Arthur, at about 3,300 feet, which was kindly given to me by Mr. C. W. Palmer. In the summer of 1894-95 several specimens were captured by Mr. P. Marshall near Wanganui,[53] and during the same season Messrs. Smithers and Hawthorne discovered the insect in considerable abundance at a locality near Silverstream, in the Wellington district. During the two following summers additional specimens were obtained near Silverstream, and I was fortunate enough to discover there a number of specimens of the larva, which furnished the material for the illustration and description of the preparatory stages of the insect given in this work. The expansion of the wings is about 2 inches. On the upper side all the wings are dark brown. The fore-wings have two broad bands of yellowish-orange, the outer one containing a This insect appears to vary a little in the extent of the yellowish-orange colouring of the upper side. It also varies in size, specimens from the North Island being slightly larger than those from the South Island. The larva feeds on a species of sedge (Galinia setifolia), which always grows abundantly in the birch forests, where the butterflies are found. When full grown the length of this caterpillar is about 1¼ inches. Its body is much attenuated at each end and rather stout in the middle; the head and tail are bifid; there are numerous straight, shallow, transverse wrinkles on each segment, especially towards the head. The colour is green, with a number of fine, paler and darker green, dorsal and lateral lines; the head and thirteenth segment are yellowish. The legs are very minute, and the prolegs of moderate size. It is extremely susceptible to the attacks of a Dipterous parasite. In fact, out of thirty larvÆ kept by Mr. Hawthorne and myself, no less than 75 per cent. were thus destroyed. This larva feeds on the leaves of the sedge, eating out long notches parallel to the veins of the leaf. These notches are the best guides to follow in searching for the larva, as the colouring of the caterpillar renders its discovery amongst the food-plant extremely difficult. The larvÆ should be looked for during the end of December or the beginning of January. The pupa is rather stout, light green, with the edge of the wing-case and the prominences formed by the back and palpi, edged with crimson and white. It is suspended by the tail to any firm object in the neighbourhood of the sedge. The perfect insect appears in February. It frequents sunny glades in the birch forest, usually at considerable elevations above the sea-level. Mr. Helms informs me that he has seen specimens near Greymouth in October, and hence concludes that there are two broods in the year. The butterfly is very difficult to capture, as it has a most provoking habit of resting on the foliage of the birch-trees, just out of the collector's reach. I am unable to explain the object of the remarkable colouring of the under side of this insect, but it is probably protective, although in what way has yet to be discovered. Genus 3.—EREBIA, Dalm."Eyes glabrous. Club of antennÆ abrupt." (Plate I., figs. 25, 26, and 27 neuration of Erebia pluto.) "An extensive and essentially Alpine genus inhabiting the mountains of Europe, Asia, North America, and South Africa. Pupa unattached amongst stem bases of grass."—(Meyrick.) We have two species in New Zealand. EREBIA PLUTO, Fereday. (Erebia pluto, Fereday. Erebia merula, Hewitson, Ent. Mo. Mag. xii. 10 (1874). Oreina othello, Fereday, Trans. N. Z. Inst. viii. 302, 304, pl. ix. (1876). Percnodaimon pluto, Butl., Ent. Mo. Mag. xii. 153 (1876); Catalogue of N. Z. Butterflies, 10.) (Plate XI., fig. 8 ?, 9 ?, 10 under side.) This fine butterfly has occurred plentifully on many mountain-tops in the South Island, from Nelson to Lake Wakatipu. It has never been observed in the North Island. The expansion of the wings of the male is 1¾ inches, of the female 2 inches. On the upper side all the wings are a very rich bronzy-black. The fore-wings have a paler patch near the apex, containing two small, and three large black ocelli with white centres; these ocelli are usually joined together. On the under side all the wings are considerably paler and greyer. The hind-wings have a series of pale spots near the termen, and a paler shade across the middle. The insect varies chiefly in the number of ocelli. On the upper side of the fore-wings there are sometimes only four, the minute ocellus on the costa being absent, whilst occasionally a small extra ocellus appears below the normal series. On the under side this last-mentioned ocellus is very frequently, but not invariably, present. In some female specimens an extremely minute ocellus may be detected on the upper surface of the hind-wings near the termen. On the under side of the hind-wings in both sexes the series of pale terminal spots are often absent, and the general depth of the colouring varies considerably. Mr. Fereday has described and figured a very interesting variation occurring in the structure of the costal veins of this species,[54] vein 11 of the fore-wings sometimes running into 12 (see Plate I., fig. 26), and sometimes being entirely absent (fig. 25). After reading Mr. Fereday's article I examined the specimens in my own collection, and found that all those taken on Mount Arthur and on Mount Peel, in the Nelson district, had veins 11 and 12 joined, whilst the two specimens I took on Mount Enys, Castle Hill, West Coast Road, had vein 11 absent. As, however, Mr. Fereday has specimens exhibiting both forms of neuration, from Castle Hill and from Mount Hutt, I do not think it likely that the peculiarity is confined to butterflies from any particular locality. Like Mr. Fereday, I have observed that the specimens having veins 11 and 12 joined, are smaller than those having vein 11 absent. The perfect insect appears in January, February and March. It frequents shingle slopes on mountains, at elevations ranging from 4,000 to 6,000 feet above the sea-level. Sometimes the butterflies occur in considerable numbers, flying in a lazy, aimless manner in the scorching sunshine, but instantly retreating into crevices between the stones when the sun is obscured. I have observed that this species is most abundant in the neighbourhood of the carpet grass, on which I fully anticipate its larva feeds. It seldom, however, settles on this grass, preferring to alight on the shingle, which, owing to the rarefied air existing at such high elevations, soon becomes intensely heated by the sun's rays. When disturbed this insect flies with considerable rapidity and thus often eludes the net, so that the capture of a good series of specimens on a rugged mountain-top is usually very exciting, if not actually dangerous work. As with many other EREBIA BUTLERI, Fereday. (Erebiola butleri, Fereday, Trans. N. Z. Inst. xii. 264; Catalogue of N. Z. Butterflies, 19.) (Plate XI., fig. 11 ?, 12 ?, 13 under side.) This interesting butterfly was described from three dilapidated specimens captured by Mr. J. D. Enys at Whitcombe's Pass, Canterbury, on March 8, 1879, at about 4,000 feet above the sea-level. From that time I believe no other specimens had been found until January, 1894, when I took quite a large number on the Humboldt Range, at the head of Lake Wakatipu, at elevations ranging from 4,000 to 5,000 feet above the sea-level. The expansion of the wings of the male is 1? inches, of the female 1½ inches. On the upper side all the wings of the male are smoky-brown; the fore-wings have a large black ocellus near the apex, enclosing two white dots, followed by a smaller ocellus towards the dorsum; the hind-wings have three black spots near the termen, sometimes enclosing white dots. Occasionally these ocelli are surrounded by a patch of deep reddish-brown. The female is much paler, with large patches of yellowish-brown surrounding the ocelli. On the under side the fore-wings of the male are smoky-brown, with an irregular blotch of reddish-brown near the apex, surrounding a small white-centred black ocellus. The hind-wings are dark reddish-brown, with several conspicuous black-edged silvery markings, and four yellowish-red spots near the termen. The under side of the female is very much paler. This butterfly varies considerably on the upper side in the number and size of the ocelli, and in the extent of the reddish-brown markings which surround them; on the under side the silvery spots on the hind-wings are also variable. The perfect insect has been taken in January and March. It evidently frequents mountains in the South Island, at elevations of about 4,000 feet, but does not appear to be generally distributed in such localities. It seldom settles on the shingle, mostly resting on the snow grass, on which its larva probably feeds. It is a smaller insect than E. pluto, and flies much more feebly. These characteristics will at once enable the collector to distinguish it from E. pluto when on the wing. Immediately a cloud obscures the sun these butterflies retreat into the tufts of the snow grass, remaining closely hidden there until the sun shines out again. This circumstance makes the capture of the insect, even in a favourable locality, a matter of considerable uncertainty, as bright sunshine is more often the exception than the rule on the summits of high mountains. |
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