Grayling, if you take your station by the side of a river, will rise nearer to you than trout, for they lie deeper, and therefore are not so much scared by an object on the bank; but they are more delicate in the choice of their flies than trout, and will much oftener rise and refuse the fly. Trout, from lying nearer the surface, are generally taken before grayling, where the water is slightly coloured, or after a flood: and in rain, trout usually rise better than grayling, though it sometimes happens, when great quantities of flies come out in rain, grayling, as well as trout, are taken with more certainty than at any other time;—the artificial fly, in such cases, looks like a wet fly, and allures even the grayling, which generally is more difficult to deceive than trout in the same river. PHYS.—As I was looking into a ditch coming down the river, which is connected with it, I saw a very large eel at the bottom, that appeared to me to be feeding on a small grayling:—are there many of this fish in the Teme, and do they breed here? HAL.—There are many of this fish in the river; but to your question, do they breed here? I must answer in the negative. The problem of their generation is the most abstruse, and one of the most curious, in natural history; and though it occupied the attention of Aristotle, and has been taken up by most distinguished naturalists since his time, it is still unsolved. PHYS.—I thought there was no doubt on the subject. Lacepede, whose book is the only scientific one on fishes I have read with attention, asserts, in the most unqualified way, that they are viviparous. HAL.—I remember his assertion, but I looked in vain for proofs. PHYS.—I do not remember any _facts_ brought forward on the subject; but tell us what you think upon it.