Essays in Natural History and Agriculture Part 13

[6] I have frequently found, when catching Trout for this purpose, that the milt and roe were not ready for exclusion; when this was the case, I put them into a wire cage, which I sunk in the water, examining the fish every week, until I found they were in a fit state for the experiment.

[7] I fancy that if the ova come in contact with the air on exclusion, they are not so readily impregnated as if they are always covered with the water, and therefore I have laid some stress on the desirableness of keeping the air excluded from the ova as much as possible.

[8] There is, however, one fact which must lead a casual observer to suppose that the ova are impregnated twelve months before exclusion. It is this: the male Par (Salmon fry) are at this season, October, full of milt, almost ready for exclusion; whilst, in the female, the ova are so small that they require a microscope to see them individually, and the whole ovary is merely like a thread, leading to the conclusion that either the milt of the male is not required for the female Par, or the ova are impregnated twelve months before exclusion. The fact is, that the milt of the Par is used to impregnate the ova of the Salmon on the sp.a.w.ning beds.

[9] When I commenced this paper I had no doubt that hybrids had been produced between the Sprod (sea Trout) and the common Trout; since then, having seen the fry said to be so produced, and on making some further inquiries, I find there is some doubt whether the female was a _Sprod_, or merely a white Trout, and therefore I cannot confidently a.s.sert (as some time ago I believed I could) that hybrid fish had already been produced. As some of my readers may not know what a _Sprod_ is, it may be necessary to explain. In the Ribble we have a fish ascending from the sea in July and August, weighing from six to ten ounces, which, in appearance at least, is a miniature Salmon. I believe the same fish is called a Whitling in Scotland. Besides this, we have a similar but larger fish, which begins to come a little earlier, and which weighs from one to three pounds; this, in the Ribble, is called a Mort (in Scotland a sea Trout). Both these fish (if they are two species) afford splendid sport to the angler, who must never consider them beaten until he has them in the landing-net. They are also delicate eating.

_Note on cross-breeding of Fish._

Since the above paper was published, the breeding of Hybrids has been successfully accomplished. I have had fish sent from two different gentlemen living on the banks of the reservoirs belonging to the Liverpool Waterworks; these were beautiful fish (three in number), more like the sea Trout than the Salmon, and the largest of them weighing two pounds. I had put them into the brooks running into the reservoirs three years before.

I also learn from a friend that a beautiful specimen of the _ombre Chevalier_ (French Char) was taken out of the Rivington reservoir.

About a thousand had been put there by me two years before.

[10] Persons conversant with the habits of birds will readily comprehend me; for the sake of those who do not, I will just observe that the flight of all the Wagtails is very peculiar, being a succession of great leaps in the air (if I may be allowed the expression), which form a series of curves, the bird rising considerably at the commencement of each effort, and sinking again at the close.

[11] The intrepid and unfortunate traveller Joseph Ritchie, who accompanied Captain Lyon's expedition to Fezzan, and died there in 1819. Mr. Ritchie was a native of Otley, and an intimate friend of Mr. Garnett and his brothers. The beautiful poem from which the quotation is taken is printed in Alaric Watts's "Poetical Alb.u.m."

[12] 1853.--I regret that in 1853, and for some years previous, we have not seen one. I fear they are extinct. The smaller kind are still numerous.

[13] The male Par is an exception to this rule.

[14] It appears to be a beautiful provision of Nature that mixture with water should increase the sphere of its action. Spallanzani found by actual experiment that three grains of the seed of a male frog might be diluted with a pint of water without destroying its stimulating power. See "Dissertations," vol. ii. p. 142, chap. 3, Ed. "Mag. Nat. History."

[15] Mr. Thomson, of Primrose.

[16] a.s.sistant Keeper of Printed Books in the British Museum.

Author of "Philological Essays," &c.

[17] The toad, when going to take a bee, points for a second or two as beautifully as the best-trained pointer before it strikes with its tongue.