. Elementary text-book of zoology, general part and special part: protozoa to insecta. Animals. Fig. l^i.—EiigUna i Idh. a ami swimming, in different states of contraction, encysted and in process of division. c,d,e. During the motile stage they possess the power of reproduction, since the individual cells give rise to daughter colonies inside the mother colony. A sexual reproduction (conjugation) has also been shown. Certain of the mother cells increase in size and divide into numerous microgonidia corresponding to spermatozoa; others grow to large ovicells, which are impregnated by th
. Elementary text-book of zoology, general part and special part: protozoa to insecta. Animals. Fig. l^i.—EiigUna i Idh. a ami swimming, in different states of contraction, encysted and in process of division. c,d,e. During the motile stage they possess the power of reproduction, since the individual cells give rise to daughter colonies inside the mother colony. A sexual reproduction (conjugation) has also been shown. Certain of the mother cells increase in size and divide into numerous microgonidia corresponding to spermatozoa; others grow to large ovicells, which are impregnated by the former, and then surround themselves with a capsule, and sink to the ground as large star-shaped cells. They also reproduce themselves during their period of inacti%'ity by fission within the cellulose capsule, while at the same time a change of colour takes place. Amongst the best known of the Volvocina are Volvox glohator, Gonium pectorale, Ste- phanospli(sr(i pliivialis. The Astasiadce are contractile unicellular Flagellata, which are allied to the Volvocinidce in their life phenomena, but they take up. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Claus, Carl, 1835-1899; Metcalf Collection (North Carolina State University). NCRS. London, Swan Sonnenschein
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectanimals, bookyear1892
