Bulletin of the United States Fish Commission, Band 1U.S. Government Printing Office, 1882 |
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abundance anal spine Anguilla animal apparatus appears April bait barrels bass blastoderm boats body branchial canal carp caudal Caudal fin caught cells cents coast color Comacchio diameter dories eels eggs embryo Entomostraca epiblast female fish fishermen fishery germinal disk Gill gill-nets Gloucester haddock half hatching haul hypoblast impregnation inches in length intestine Island Lake large number lateral line latter layer length of head lower jaw male eels March membrane menhaden mesoblast miles mouth nearly nets notochord nucleus observed opercle organs ovaries ovum oyster pectoral PLATE pond pounds preopercle Prof Protozoa rays river S. F. Baird salmon Saprolegnia scales schooner season seen segmentation cavity shad shore side snout Spanish mackerel spawn species specimens spermatozoa streams Syrski taken teeth temperature tion trawls trout upper ventrals vesicle vessels vitellus whitefish yelk young eels young fish zoospores
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Seite 236 - I agree with him that it may be taken as proved that all the materials of such deposits, with the exception, of course, of the remains of animals which we now know to live at the bottom at all depths, which occur in the deposit as foreign bodies, are derived from the surface.
Seite 77 - Their mode of propagation is still unknown. So much only is certain, that they do not spawn in fresh water, that many full-grown individuals, but not all, descend rivers during the winter months, and that some of them, at least, must spawn in brackish water or in deep water in the sea...
Seite 430 - The apex of the latter then opens and the zoosporangia are emitted. Each zoospore, as it leaves the zoosporangium, is usually in active motion, being propelled by the rapid lashing of two vibratile cilia which are attached to one point of its surface. After a few minutes it becomes quiescent and surrounds itself with an extremely delicate transparent coat. But this repose is of a very short duration, as it soon emerges from its envelope, and moves about even more actively than before.
Seite 442 - Leptomitus lacteus, but which is so closely allied to Saprolegnia that Pringsheim places it in that genus, is widely spread in running waters, where it grows on all sorts of dead organic substances. A factory for making spirit from turnips was established near Schweidnitz, in Silesia, and the refuse was poured into an affluent of the River Westritz, which runs by Schweidnitz. The result was such a prodigious growth of Leptomitus that the fungus covered some 10,000 square feet at the bottom of the...
Seite 431 - The oospore, or oospores, thus formed eventually become invested by a thick cellulose coat. Before this happens, in some forms of Saprolegnia, slender twig-like branches are given off either from the stalk of the oosporangium or from an adjacent hypha, and the terminal portion of one or more of these twigs applies itself to the oosporangium. This terminal portion becomes shut off from the rest of the twig by a transverse septum, and is an Antheridium.
Seite 425 - Government, rather than for ourselves, to consider whether, under these circumstances, any steps are desirable for the purpose of remedying these pollutions. It is merely our duty to point out the danger which arises from them. The second point to which we desire to draw attention is the remarkable outbreak of a disease among the salmon of many rivers. The disease was noticed originally in the autumn and spring of 1877 in two rivers, the Esk and the Nith, which flow into the Solway Firth. It soon...
Seite 374 - Gentlemen executors of this my last will and testament, in witness whereof I have hereunto put my hand and seal, this thirty-first day of October, in the year of our Lord, One Thousand Seven Hundred and Seventy-five.
Seite 430 - After a fewminutes it becomes quiescent and surrounds itself with an extremely delicate transparent coat. But this repose is of a very short duration, as it soon emerges from its envelope, and moves about even more actively than before. It has now an elongated oval shape, and has two cilia which proceed from one side of the oval. This second active state may last for a day, or perhaps two ; and it is obvious that, from the activity of the motion of the zoospores, to say nothing of accidental currents,...
Seite 443 - If we allow only 1,000 fruiting hyphae for every square inch, we shall have 288,000 for the whole surface, which, at the same rate as before, gives over 10,000,000 spores for a day's production, or enough to provide a spore to every cubic foot of a mass of water 100 feet wide and 5 feet...
Seite 440 - ... readily explicable should this supposition turn out to be well founded. Another possibility was suggested by the same fact. We know that the spores of the Empusa, a fungus which attacks living flies, germinate and bore through the cuticle in much the same fashion as the Saprolegnia enters dead flies. But the hypha of the Empusa, which has thus entered the fly, immediately breaks up into short joints, which diffuse themselves through the body of the fly and everywhere multiply by division, until...