Volume Ii Part 53 (1/2)
In damp meadows the moth is out in May and June, but in marshes it does not appear, as a rule, until July, and may be found in early August. The marsh specimens, which are sometimes rather large in size, have been referred to _pal.u.s.tris_, Oberthur, and are treated by Tutt (_Nat. Hist. Brit. Lep._, vol. i.) as a sub-species.
[Ill.u.s.tration]
2 Pl. 146.
1, 2. TRANSPARENT BURNET.
3. SCOTCH BURNET.
4, 5. NEW FOREST BURNET.
6-9. FIVE-SPOT BURNET.
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2 Pl. 147.
1, 2. NARROW-BORDERED FIVE-SPOT BURNET.
3-5. SIX-SPOT BURNET.
6, 7. SCARCE FORESTER.
8, 9. THE FORESTER.
10, 11. CISTUS FORESTER.
{339} In the British Isles, the species is apparently confined to England and North Wales. In the former country it is locally common in most of the southern counties; still more local in the eastern counties, and northwards to Lancas.h.i.+re and Yorks.h.i.+re. There are records from Armagh and Fermanagh, but Kane appears to doubt the occurrence of the species in Ireland. There is no doubt that the next species has frequently been mistaken for the present one, therefore the actual range of _trifolii_ in the British Isles has probably not been fully ascertained.
NARROW-BORDERED FIVE-SPOT BURNET (_Zygaena lonicerae_).
As will be seen from the two specimens represented by Figs. 1 [male] and 2 [female] on Plate 147, this species bears considerable resemblance to ab.
_orobi_ of _Z. trifolii_. The chief differences are in the rather longer fore wings and the more pointed tips of the hind pair; the borders of the hind wings are often narrower. In a broad way, it may be stated that the general tone of colour in the male of _lonicerae_ is bluer than that of _trifolii_. The union of any two or more spots is rarely seen in this species in Britain, but specimens with all the spots joined together have certainly been noted. A yellow form, ab. _citrina_, Speyer (= _flava_, Oberthur), is known on the continent, and Barrett states that it has occurred in England. In ab. _lutescens_, Hewett, the hind wings are orange.
Ab. _eboraceae_, Prest, is semi-transparent, steel blue; the spots and the hind wings are pink, the border of the hind wings brown, and the fringes of all the wings are whitish.
The caterpillar (Plate 145, Fig. 2) is very similar to that of the last species, but the black marks on the sides are heavier, and the hairs of the body are longer. It feeds on trefoils and clover, and sometimes pa.s.ses two winters before becoming full grown. The coc.o.o.n, which is attached to stems of gra.s.s, etc., is generally placed well up above the ground, so that it is readily seen. {340}
The moth, which is out in late June and in July, occurs in woods and plantations; also said to be found in meadows, and on rough waste ground, as well as in marshes and salterns. The distribution is much as in the last species, but it is plentiful in East Yorks.h.i.+re, and the range extends to c.u.mberland and Northumberland.
SIX-SPOT BURNET (_Zygaena filipendulae_).
This species (Plate 147, Figs. 3-5) is the most generally common of our Burnets. Perhaps the most frequent form of variation in the spots of the fore wings is that in which the outer pair run together, and so form a blotch; but union of the middle pair is not an uncommon occurrence. In ab.
_cytisi_, Hubner, the three pairs of spots are each united, so that the fore wings have three separate blotches, and when these are of a dull scarlet instead of the usual crimson, ab. _ramburi_, Lederer, is represented. Occasionally, all the spots are united, as in ab. _cytisi_, and the blotches thus formed are connected by reddish streaks in various modifications leading up to ab. _conjuncta_, Tutt, which has all the spots merged into a large blotch, extending over the disc of the fore wings. From the normal crimson, the spots and the hind wings vary now and then to orange (_aurantia_, Tutt), or to yellow (ab. _flava_, Robson = _cerinus_, Robson and Gardner); intermediate shades between these two extremes, and the typical coloration, are rather more frequent. I am indebted to Mr. R.
Adkin for the loan of the example of the yellow form shown on Plate 148, Fig. 6. Pink, and orange, forms have been noted from various parts of England, but they seem to occur, or have been found, more especially in Cambridge and the north-east corner of Ess.e.x. Fig. 7, Plate 148, represents an example of ab. _chrysanthemi_, Hubner, and is copied from Oberthur's _Etudes d'Entom._, xx., Plate 8, Fig. 134. A few specimens referable to this form, probably not exceeding half a dozen altogether, have been recorded as taken in England. In typical _filipendulae_ the dark blue border of the hind wings is narrow, but in ab. _hippocrepidis_, Stephens (_tutti_, Rebel), the borders are rather broad. Another character of this form is that the nervule upon which the sixth spot is placed is here of the ground colour, and therefore divides the spot. (Plate 147, Fig. 3.) At Northwood, Middles.e.x, I have found this form in May and June, and also in the Weybridge district, Surrey, in late July; and, it may be added, there was a flouris.h.i.+ng colony of _Z. trifolii_ hard by in each locality. For this reason, plus the fact that _trifolii_ [male] is known to pair with _filipendulae_ [female], I hold the opinion that _hippocrepidis_ is a hybrid. It may be noted here that hybrids have been raised from the crossing of _filipendulae_ and _lonicerae_; the s.e.xes of _lonicerae_ and _trifolii_ pair somewhat readily, and the hybrid offspring of such pairings are fertile.
[Ill.u.s.tration]
2 Pl. 148.
1. NEW FOREST BURNET, AB. _CONFUSA_.
2, 3, 4, 5. FIVE-SPOT BURNET, VARS.
6, 7. SIX-SPOT BURNET, VARS.
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