ON THE DISTRIBUTION OF TROUT IN SUFFOLK.
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In due course the eggs hatch, when the baby Trout in their first stage are known as alevins. For long they are under an inch in length and very helpless ; the mouth organs do not develop, but under the body of each little fish is a considerable yolk-sac, the contents of which are gradually assimilated as nourishment. As soon as this sac is quite absorbed,the mouth develops into being ; and the fish, now perfected miniatures of the adult, are collectively called fry. The rate of its increase in size is in direct ratio to the food-supply and suitability of the surrounding water. Like the stag, it attains its prime in about six years, and remains in that condition for a few more, after which period it declines, ceases to breed, and grows lean and lanky with a great hooked lower jaw.
Their food consists of almost every kind of small aquatic life, such as freshwater Shrimps (Asellus aquaticus, Linn.), worms, snails, spiders, small fish, beetles and the subaqueous stages of various other insects, with any flies and caterpillars that they are able to annex from the surface of the water. Old Trout will take also shrews, frogs, smaller editions of their own kind, and in fact, anything they are capable of Coming at and swallowing. In the everlasting struggle for existence, very numerous enemies attack this fish : their ova are consumed by wading birds and cannibalistic fish, including eels ; alevins have to run the gauntlet of other predatory fish, kingfishers, herons and, in places, such birds as grebes and cormorants ; finally the fry fall to Otters, and adults to man himself. They will thrive in almost any quite-pure waters, throughout the temperate zone ; but, whenever they occur in lakes or sluggish streams, fast running affluents are necessary for their spawning and, of course, slack competition helps their growth.
LUMINOUS BY
CLAUDE
MORLEY,
CENTIPEDS. F.E.S.,
F.G.S.,
F.Z.S.
THE investigations of William Kirby of Barham, F.R.S., into the economy of these repulsive but most interesting Myriapoda, have been hitherto overlooked by modern scientists ; in his day, they feil within the scope of Insects and the typical species bcolopendra electrica, Linn., relegated to the genus Geophilus - b a m ° u e l l e in 1819, p. 117) was doubtless confused with allied ones. Kirby found both carrots, " which form a valuable part of the crop of sand-lands in Suffolk," and parsnips to be much mjured by the small Centiped, Geophilus electricus, and another myriapod Polydesmus complanatus, Linn., that eat into the upper r00ts rimV ( K i r b y a n d S P e n c e > Introd. Entom., Ed. 1859, ln T ^ e former is also carnivorous, for it assimilates the ommon Earthworm (.Lumbricus terrestris, Linn.) and " the Rev.