. The Protozoa. Protozoa. THE INFUSORIA 199 together above the developing buds, which, when ripe, break through the birth-opening left in the covering membrane (Fig. in). In some cases the buds are multiple, again single, and a number may develop at the same time within the brood-sac (Acineta, Opliryodendrou). The embryos thus formed are variously ciliated in the different genera. In some they are holotrichous, in others hypotrichous, and in others peritrichous {c, d).. Fig. in.—Endogenous budding in Suctona. [BUTSCHLI.] A-B. Two stages in the formation of the bud in Tokopkrya quadripartita CI
. The Protozoa. Protozoa. THE INFUSORIA 199 together above the developing buds, which, when ripe, break through the birth-opening left in the covering membrane (Fig. in). In some cases the buds are multiple, again single, and a number may develop at the same time within the brood-sac (Acineta, Opliryodendrou). The embryos thus formed are variously ciliated in the different genera. In some they are holotrichous, in others hypotrichous, and in others peritrichous {c, d).. Fig. in.—Endogenous budding in Suctona. [BUTSCHLI.] A-B. Two stages in the formation of the bud in Tokopkrya quadripartita CI. and Lach. c. The swarm-spore liberated. C. Buds in Acineta tuberosa Ehr. d. A swarm-spore liberated. Conjugation occurs here as in the Ciliata, but the process rests upon the single observations of Maupas, who shows, however, that it differs in no essential features from that already described. III. INTER-RELATIONS OF THE INFUSORIA In searching for the origin of the Ciliata, the naturalists of thirty years ago had an apparent advantage, in that the supposed ciliated girdle of the Dinofiagellidia offered a direct transition to the peritrichous Ciliata, which, accordingly, were regarded as coming from the flagellate stem at a comparatively late date. Unfortunately for the theory, however, it was ascertained by Butschli ('85) and others that the girdle of cilia is only a vibrating flagellum in the transverse groove. In other directions the search for the origin of these forms has been almost equally vain. The singularly con- servative structure which the ciliate body presents leaves but little clue to their ancestry. The universal presence of macro- and micro- nuclei is paralleled by only one other known case, the almost universal reproduction by transverse division is met with elsewhere but rarely. The sole possibility which presents itself is that the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability -
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Keywords: ., bookauthorcalkinsg, bookcentury1900, bookdecade1900, bookyear1901
