in myriads on the smooth ledges of rock, where the water runs gently a few inches deep. These are abundant everywhere: but I never saw so many of them as in the exquisite Cother brook, near Middleham, in Yorkshire. In that delicious glen, while wading up beneath the ash-fringed crags of limestone, out of which the great ring ouzel (too wild, it seemed, to be afraid of man) hopped down fearlessly to feed upon the strand, or past flower-banks where the golden globe-flower, and the great blue geranium, and the giant campanula bloomed beneath the white tassels of the bird-cherry, I could not tread upon the limestone slabs without crushing at every step hundreds of the delicate Mystacide tubes, which literally paved the shallow edge of the stream, and which would have been metamorphosed in due time into small sooty moth-like fairies, best represented, I should say, by the soft black-hackle which Mr. Stewart recommends as the most deadly of North-country flies. Not to these, however, but to the Phryganeæ (who, when sticks and pebbles fail, often make their tubes of sand, e.g. _P. flava_), should I refer the red-cow fly, which is almost the only autumn killer in the Dartmoor streams. A red cowhair body and a woodcock wing is his type, and let those who want West-country trout remember him. Another fly, common on some rocky streams, but more scarce in the chalk, is the ‘Yellow Sally,’ which entomologists, with truer appreciation of its colour, call _Chrysoperla viridis_. It may be bought at the shops; at least a yellow something of that name, but bearing no more resemblance to the delicate yellow-green natural fly, with its warm grey wings, than a Pre-Raphaelite portrait to the human being for whom it is meant. Copied, like most trout flies, from some traditional copy by the hands of Cockney maidens, who never saw a fly in their lives, the mistake of a mistake, a sham raised to its tenth power, it stands a signal proof that anglers will never get good flies till they learn a little entomology themselves, and then teach it to the tackle makers. But if it cannot be bought, it can at least be made; and I should advise everyone who fishes rocky streams in May and June, to dye for himself some hackles of a brilliant greenish-yellow, and in the most burning sunshine, when fish seem inclined to rise at no fly whatsoever, examine the boulders for the Chrysoperla, who runs over them, her wings laid flat on her back, her yellow legs moving as rapidly as a forest-fly’s; try to imitate her, and use her on the stream, or on the nearest lake. Certain it is that in Snowdon this fly and the Gwynnant Hydropsyche will fill a creel in the most burning north-easter, when all other flies are useless; a sufficient disproof of the Scotch theory—that fish do not prefer the fly which is on the water. {74}