There is also in _Northumberland_, a _Trout_, called a _Bull Trout_, of a much greater length and bignesse then any in these Southern parts; and there is in many Rivers that relate to the Sea, _Salmon Trouts_ as much different one from another, both in shape and in their spots, as we see Sheep differ one from another in their shape and bigness, and in the finess of their wool: and certainly as some Pastures do breed larger Sheep, so do some Rivers, by reason of the ground over which they run, breed larger _Trouts_.
Now the next thing that I will commend to your consideration is, That the _Trout_ is of a more sudden growth then other fish: concerning which you are also to take notice, that he lives not so long as the _Pearch_ and divers other fishes do, as Sir _Francis Bacon_ hath observed in his History of life and death.
And next, you are to take notice, that after hee is come to his full growth, he declines in his bodie, but keeps his bigness or thrives in his head till his death. And you are to know that he wil about (especially before) the time of his Spawning, get almost miraculously through _Weires_ and _Floud-Gates_ against the stream, even through such high and swift places as is almost incredible. Next, that the _Trout_ usually Spawns about _October_ or _November_, but in some Rivers a little sooner or later; which is the more observable, because most other fish Spawne in the Spring or Summer, when the Sun hath warmed both the earth and water, and made it fit for generation.
And next, you are to note, that till the Sun gets to such a height as to warm the earth and the water, the _Trout_ is sick, and lean, and lowsie, and unwholsome: for you shall in winter find him to have a big head, and then to be lank, and thin, & lean; at which time many of them have sticking on them Sugs, or _Trout_ lice, which is a kind of a worm, in shape like a Clove or a Pin, with a big head, and sticks close to him and sucks his moisture; those I think the _Trout_ breeds himselfe, and never thrives til he free himself from them, which is till warm weather comes, and then as he growes stronger, he gets from the dead, still water, into the sharp streames and the gravel, and there rubs off these worms or lice: and then as he grows stronger, so he gets him into swifter and swifter streams, and there lies at the watch for any flie or Minow that comes neer to him; and he especially loves the _May_ flie, which is bred of the _Cod-worm_ or _Caddis_; and these make the _Trout_ bold and lustie, and he is usually fatter, and better meat at the end of that month, then at any time of the year.