Inhaltsangabe:
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1918 Excerpt: ...such water may teem with animal life, just such life as the microscopist desires. It is not possible to point out the exact locality where an abundance of microscopic animals may be found. They appear to be a law to themselves. The pond that may seem a likely place, may for some unknown reason be barren; while another to all appearance worthless may prove of great value. The food-supply may be the cause, or the temperature, or freedom from enemies, or some other thing. The microscopist can take his dips to the instrument, only hoping that he has the success for which he has wished. There is one place, however, to which he need never go. This is the thick mud at the bottom. Here some Rhizopods may be collected, but Infusoria and other creatures rarely. They prefer to wander among the leaflets of the aquatic plants, to swim in the clearer depths, or to seek their smaller prey nearer the surface. Some forms of Rhizopods can be taken only nearer the surface among the plants. To carry home a bottle full of mud-and-water with nothing else is commonly a useless labor. Rather thrust the dipper among the aquatic weeds, and after several gentle turns and twists to loosen the plants and to stir up the water about them, transfer the dipperful to the bottle, and hope for the best. The majority of microscopic animals may be collected in this way better than in any other, except by washing the plants and preserving the rinsing; but this is a rather more laborious method, and takes rather more time, a matter of some importance if the microscopist's leisure is limited. These methods, however, are not restricted to Infusoria. In my vicinage, certain ponds with which I am well acquainted are always entirely free from Lemna and Spirodela, while others, smaller and shallower an...
Reseña del editor:
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1918 Excerpt: ...such water may teem with animal life, just such life as the microscopist desires. It is not possible to point out the exact locality where an abundance of microscopic animals may be found. They appear to be a law to themselves. The pond that may seem a likely place, may for some unknown reason be barren; while another to all appearance worthless may prove of great value. The food-supply may be the cause, or the temperature, or freedom from enemies, or some other thing. The microscopist can take his dips to the instrument, only hoping that he has the success for which he has wished. There is one place, however, to which he need never go. This is the thick mud at the bottom. Here some Rhizopods may be collected, but Infusoria and other creatures rarely. They prefer to wander among the leaflets of the aquatic plants, to swim in the clearer depths, or to seek their smaller prey nearer the surface. Some forms of Rhizopods can be taken only nearer the surface among the plants. To carry home a bottle full of mud-and-water with nothing else is commonly a useless labor. Rather thrust the dipper among the aquatic weeds, and after several gentle turns and twists to loosen the plants and to stir up the water about them, transfer the dipperful to the bottle, and hope for the best. The majority of microscopic animals may be collected in this way better than in any other, except by washing the plants and preserving the rinsing; but this is a rather more laborious method, and takes rather more time, a matter of some importance if the microscopist's leisure is limited. These methods, however, are not restricted to Infusoria. In my vicinage, certain ponds with which I am well acquainted are always entirely free from Lemna and Spirodela, while others, smaller and shallower an...
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