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The difference of sex merely corresponds to duplex and simplex conditions of nucleus, but it is curious that the simplex condition in the gametes occurs in both ova and sperms. In Daphnia and Rotifers the facts are different. Parthenogenesis occurs when food supply is plentiful and temperature high.
It is in the long black droughts, when the water is foul from lowness, and not from height, that Hydras and Desmidiae, and Rotifers, and all uncouth pseud- organisms, bred of putridity, begin to multiply, and the fish are sick for want of a fresh, and the cunningest artificial fly is of no avail, and the shrewdest angler will do nothing except with a gross fleshly gilt-tailed worm, or the cannibal bait of roe, whereby parent fishes, like competitive barbarisms, devour each other's flesh and blood perhaps their own.
I ought to, for I don't know anything else." "It must be most interesting." "Last week I did the fresh water lakes and got some very good results. Professor Wilder and his wife are doing rotifers. They're stopping " "In tents?" said Frank with interest. "Tents! No. In quite the sweetest cottage you ever saw. I sleep on a sofa in the porch. What put tents into your head?"
But that the insects may have descended from some low worms is not improbable when we reflect that the Syllis and allied genera of Annelides bear appendages consisting of numerous joints; indeed, the strange Dujardinia rotifers, figured by Quatrefages, in its general form is remarkably like the larva of Chloëon.
Fabre has proved this: let the temperature suddenly fall twenty degrees: the eggs of Geotrupes and the larvae of the cockchafer or the rose-beetle endure such vicissitudes of temperature with impunity; contracted and stiffened into little masses of ice, but not destroyed, they revive in spring no less than the eel fry, the rotifers, or the tardigrades.
The plant grows rapidly and is endowed with much vitality, for it resists changes of temperature to a remarkable degree. Vaucheria affords a choice hunting ground to the microscopist, for its tangled masses are the home of numberless infusoria, rotifers, and the minuter crustacea, while the filaments more advanced in age are usually thickly incrusted with diatoms.
The air which we breathe is loaded with impalpable dust that awaits, for ages perhaps, proper conditions of heat and moisture to give it an ephemeral life that it will lose and acquire by turns. In 1707, Spallanzani found it possible, eleven times in succession, to suspend the life of rotifers submitted to desiccation, and to call it back again by moistening this organic dust with water.
Here is a fine confession of intellectual weakness; but what an inexplicable frame of mind is that of belief. As for Rotifers and Tardigrades being spontaneously generated, my mind can no more digest such statements, whether true or false, than my stomach can digest a lump of lead. Dr.
Again, the males of most Rotifers have no digestive apparatus; as a German naturalist has remarked, they devote themselves entirely to the "Minnedienst," and are to be reckoned among the few realisations of the Byronic ideal of a lover.
I don't suppose she ever heard of rotifers. I never did. What are they?" "Insects, I fancy," said Sir Lucius. "I daresay Priscilla would know. Shall I send for her?" "No," said Lord Torrington. "I don't care what rotifers are. Let's finish our cigars outside, Lentaigne. It's infernally hot." Frank had finished his cigarette.
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