It will be observed that one of the points in this curious speculation rests on the green dress of the fairies. I do not call attention to it with any Quixotic purpose of disputing the conclusion it assists; it is far more interesting as one feature of the general subject of fairies' attire. The Welsh fairies are described with details as to colour in costume not commonly met with in fairy tales, a fact to which I have before alluded. In the legend of the Place of Strife, the Tylwyth Teg encountered by the women are called 'the old elves of the blue petticoat.' A connection with the blue of the sky has here been suggested. It has also been pointed out that the sacred Druidical dress was blue. The blue petticoat fancy seems to be local to North Wales. In Cardiganshire, the tradition respecting an encampment called Moyddin, which the fairies frequented, is that they were always in green dresses, and were never seen there but in the vernal month of May. There is a Glamorganshire goblin called the Green Lady of Caerphilly, the colour of whose dress is indicated by her title. She haunts the ruin of Caerphilly Castle at night, wearing a green robe, and has the power of turning herself into ivy and mingling with the ivy growing on the wall. A more ingenious mode of getting rid of a goblin was perhaps never invented. The fairies of Frennifawr, in Pembrokeshire, were on the contrary gorgeous in scarlet, with red caps, and feathers waving in the wind as they danced. But others were in white, and this appears to be the favourite hue of modern Welsh fairy costume, when the Tylwyth Teg are in holiday garb. These various details of colour are due to the fervour of the Welsh fancy, of course, and perhaps their variety may in part be ascribed to a keener sense of the fitness of things among moderns than was current in earlier times. White, to the Welsh, would naturally be the favourite colour for a beautiful creature, dancing in the moonlight on the velvet sward. The most popular pet name for a Welsh lass is to-day exactly what it has been for centuries, viz., Gwenny, the diminutive of Gwenllian (Anglicised into Gwendoline)--a name which means simply white linen; and the white costume of the favourite fairies undoubtedly signifies a dress of white linen. This fabric, common as it is in our day, was in ancient times of inestimable value. In the Mabinogion, linen is repeatedly particularised in the gorgeous descriptions of fabled splendour in princely castles--linen, silk, satin, velvet, gold-lace, and jewels, are the constantly-recurring features of sumptuous attire. In his account of the royal tribes of Wales, Yorke mentions that linen was so rare in the reign of Charles VII. of France (i.e., in the fifteenth century) 'that her majesty the queen could boast of only two shifts of that commodity.' The first cause of the fairies' robes being white is evidently to be discerned here; and in Wales the ancient sentiment as to whiteness remains. The Welsh peasantry, coarsely and darkly clad themselves, would make white a purely holiday colour, and devise some other hue for such commoner fairies as the Bwbach and his sort: