By most authors _filipendulae_ is regarded as the type of the genus _Zygaena_, Fabricius; but others refer this species, and its allies, to the genus _Anthrocera_, Scopoli, using the Fabrician genus for _phegea_, Linnaeus. The latter species and its allies are perhaps more frequently referred to _Syntomis_, Ochsenheimer, the typical genus of the family Syntomidae, the systematic position of which is near the Arctiidae. It may be added that _S. phegea_, and also _Naclia ancilla_, have been reported as British. There does not seem, however, to be any reason to suppose that the occurrence of either species in Britain could be other than accidental. {334} THE TRANSPARENT BURNET (_Zygaena purpuralis_). Two Welsh specimens are depicted on Plate 146, Figs. 1 and 2; these are of the typical form. A rare aberration has the spots and the hind wings more or less suffused with blackish (ab. _obscura_, Tutt), but a still rarer variety has the crimson of spots and hind wings replaced by yellow (ab. _lutescens_, Tutt). Newman in 1861 referred an Irish specimen to _achilleae_, but a little later, after seeing other examples, in the same year he changed the name to _nubiginea_. Birchall (_Ent. Mo. Mag._, iii. pt. i.) figured four forms of the species from Ireland; his _minos_ (Figs. 5a and 5b) seems to represent two modifications of ab. _interrupta_, Staudinger, in which form the red blotches are widely separated or interrupted by the ground colour; and his _nubigena_ is made up of more or less typical _purpuralis_ (Fig. 6a), and a variety (Fig. 6b), with red marks between the lower and central blotches. The caterpillar (Plate 145, Fig. 1) is dark green inclining to olive above and paler below; the spots are black (outer row) and yellow (inner row); the line along the back is obscure whitish; hairs, whitish. It feeds on thyme and burnet saxifrage (_Pimpinella_). _Trifolium_ and _Lotus_ have also been given among other food plants. In late summer, and after hibernation, in the spring. The moth flies in June, and is locally common in Ireland (Clare and Galway), Wales (Abersoch), and Scotland (Oban, Loch Etive). It has been reported from Tintagel, Cornwall, and possibly, as suggested by Tutt, these Cornish specimens may turn out to be _Z. achilleae_, the latest addition to our small band of Burnets. Perhaps the Scottish specimens recorded as _purpuralis_, or at least some of them, may prove to be _achilleae_. This species was figured by Brunnich, in 1763, as _purpuralis_, and authorities are now agreed that this name must be adopted in place of _pilosellae_, Esper (1781), or _minos_, Fuessly (1782). {335} SCOTCH OR MOUNTAIN BURNET (_Zygaena exulans_).