The caterpillar is dull hazel or chocolate brown, often tinged with green; a row of whitish dots on each side of a series of pale spots along the middle of the back; rings 4 and 8 barred with black-brown or dusky rust colour. Sometimes the general colour is green. (Adapted from Fenn.) It feeds in July and August, or even later, on oak and birch, sometimes on alder and sallow. The moth is out in May and June, earlier or later in some seasons. In Britain apparently confined to England, where it occurs locally, in woods, from Worcestershire {315} southwards to Kent and Cornwall, and eastward to Norfolk and Suffolk. In the New Forest, Hampshire, where it is often plentiful, it may be seen on the boles of trees, but is more easily obtained after dark when it comes to the sugar patch. SQUARE SPOT (_Tephrosia consonaria_). Two examples of this species will be found on Plate 137, Figs. 3 [male], 4 [female]. There is variation in the greyish or brownish speckling of the wings, and this in some typical examples is so sparse that the wings appear to be almost white with brownish basal band and brownish markings on the outer area; the most conspicuous of the latter being the middle square spot between the second and submarginal lines, more or less distinct in all forms, to which the English name refers. In other specimens the wings are, especially the front pair, densely covered with the dark speckling. Some Surrey specimens, chiefly from the Leith Hill district, have an ochreous tinge; and quite recently a black form of the species has occurred in a wood near Maidstone, in West Kent. The last phase of aberration seems to be unknown in any other part of Britain, and also, I believe, elsewhere. The egg (Plate 138, Fig. 2) is yellowish green when laid; later it becomes yellow, and orange red markings appear, chiefly at one end. The somewhat wrinkled caterpillar is ochreous brown above, inclining to greyish between the rings; an ochreous line along the middle of the back is only clearly defined on the front rings; the under side is greenish ochreous, and sometimes this colour extends to the upper side also; the head, which is notched on the crown, is pale ochreous, more or less marked with brown. It feeds at night, in June and July, on birch, beech, oak, pine, etc. {316}