. Zoology for high schools and colleges. Zoology. 34 ZOOLOGY. its body. The Amoeba reproduces its kind by simple di- vision, as seen in Amcela sphmrococcus Haeckel (Fig. 11). This species, unlike others, so far as known, becomes encysted {B), then breaks the cell-wall and becomes free as at A. Self-division then begins as at C, the nucleus doubling it- self, until at Z) as and D b we'have as the result two individ- uals. Order 1, Forarainifera.'âBesides Ammha, several other forms, either naked or shelled, produce, by division of an in- ner portion of the body, numbers of ciliated young, as in
. Zoology for high schools and colleges. Zoology. 34 ZOOLOGY. its body. The Amoeba reproduces its kind by simple di- vision, as seen in Amcela sphmrococcus Haeckel (Fig. 11). This species, unlike others, so far as known, becomes encysted {B), then breaks the cell-wall and becomes free as at A. Self-division then begins as at C, the nucleus doubling it- self, until at Z) as and D b we'have as the result two individ- uals. Order 1, Forarainifera.'âBesides Ammha, several other forms, either naked or shelled, produce, by division of an in- ner portion of the body, numbers of ciliated young, as in the naked Pelomyxa, in certain many-chambered Fora- minifera, and in CollosphcB- ra. An example may be seen in the European Pelo- myxa palustris Greef (Fig. 13). This creature lives in the mud at the bottom of fresh-water pools, and when first seen resembles little dark balls of mud a milli- metre in diameter. Instead of one nucleus, there are numbers of them, and nu- merous contractile vacuoles Fig. Vj.âPelomyxa palustris. A, a, cieai z,,, , -,, a â¢-i ±^ ti cortical portion; 6, diatoms enclosed in the nlled. With a nUld., tOgetlier body-mass. 5, amoeba-lilce bodies orisinatine -li â i mr from the nuclei, whicli after leaving tlie body With SplCUleS. J ne yOUng pass into monad-iike forms, C; n, nucleus; â__ _j. flââj. oTvimVio Ii'Vq / 0^ c, contractUe vesicle.âAfter Greef. ^re at Qrst amceba-llke (±1), originating as " shining bodies," which have resulted from the self-division of the nuclei. These amoeba-like bodies finally assume an active, monad-like stage C, and move about by means of a cilium or lash. We now come to the shelled Amoebse, or genuine For am i- nifera. A common type is Arcella, whicli secretes a one- chambered silicious shell, found in fresh water, and a representative of the monothalamous, or one-chambered, Foraminifera; while the many-chambered forms are marine, of which Globigerina huUoides (Fig. 13), found floating on the surface
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