. Zoology : for students and general readers . Zoology. THE FLAGELLATE INFUSORIA. 33 The first sign of fission is a bulging out of the collar, which becomes still more bell-shaped. The flagellum next disappears. Then marks of self-division appear in a nar- row, slight furrow (^4:7, B, e), extending from the front half way back along the middle of the body. Meanwhile the collar, which had become conical, expands, and, most striking change of all, two new flagella appear. Then the collar splits into two (Fig?-17,0), and soon the two new Oodo- sigffl become perfected, when they split asunder
. Zoology : for students and general readers . Zoology. THE FLAGELLATE INFUSORIA. 33 The first sign of fission is a bulging out of the collar, which becomes still more bell-shaped. The flagellum next disappears. Then marks of self-division appear in a nar- row, slight furrow (^4:7, B, e), extending from the front half way back along the middle of the body. Meanwhile the collar, which had become conical, expands, and, most striking change of all, two new flagella appear. Then the collar splits into two (Fig?-17,0), and soon the two new Oodo- sigffl become perfected, when they split asunder, and become like the original Codosiga. Such is the nsual mode of mul- tiplication of the species in the monads. A few monads have been observed to become encysted, and to break up into excessively minute bodies, from which new monads have grown. Two individuals of the same form (Heteromita) in certain stages fasten themselves together, the larger absorbing the smaller as if conjugating, like Desmids, the compound body resulting becoming en- cysted ; finally the contents of the cyst become divided into €rither large or minute germs {zoospores) which as- sume the parent form. The researches of Messrs. Dallinger and Drysdale on this Heteromita have proved that while the mature forms may be destroyed at a temperature of 61°— 80° 0., the motile germs, with a diameter of ^oaoad of an inch, may be heated to 148° C, without perishing. Nodiluca (Fig. 22) has been proved by Cienkowski to be an enormous monad. It is a highly phosphorescent organ- ism, so small as scarcely to be seen with the naked eye, be- ing from ^ to 1 mm. (-01 to -04 inch) in diameter. It occurs in great numbers on the surface of the sea. It has a nearly spherical jelly-like body, with a groove on one side from which issues a curved filament, used in locomotion. Near the base of this filament is the mouth, having on one side a tooth-like projection. Connecting with the mouth is an oes-. 22.—Nodiluca miliari
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectzoology, bookyear1879
