. Fresh-water biology. Freshwater biology. 164 (165) Reproduction by zoospores: chromatophore of many radially- placed rods or segments united beneath the surface. Scotinosphaera Klebs. Zoospores fusiform; their production preceded by a contraction of tile ciiromatopiiore to the center, about which there is a granular substance; zoospores penetrate some water plant or germinate in tiie water. Resting cells occur which have one or more thicken- ings of the membrane. It was first found in the dead leaves and branches of Hypniim, and its normal habitat is probably in the tissues of some higher wa
. Fresh-water biology. Freshwater biology. 164 (165) Reproduction by zoospores: chromatophore of many radially- placed rods or segments united beneath the surface. Scotinosphaera Klebs. Zoospores fusiform; their production preceded by a contraction of tile ciiromatopiiore to the center, about which there is a granular substance; zoospores penetrate some water plant or germinate in tiie water. Resting cells occur which have one or more thicken- ings of the membrane. It was first found in the dead leaves and branches of Hypniim, and its normal habitat is probably in the tissues of some higher water plant, but it occurs fre- quently in the water and may be cultivated with ease. Fig. 193. Scotinosphaera paradoxa Klebs. X about 265. (After Klebs.) 165 (164) Reproduction by copulation of isogametes and in some cases by zoospores. ... 166 166 (167) Chromatophore a parietal layer with many pyrenoids, later show- ing a network. Membrane with cellulose projections. Chlorochylrium Cohn. Cells spherical or slightly irregular; chromatophore with many inwardly projecting portions containing many pyrenoids. The zoospores are liberated singly; the gametes escape together while still enveloped by the inner lining to the membrane in which they copulate. Chlorochytriuvi occurs in the intercellular spaces of Lemna. In some species a cellulose projection extends to the surface of the epidermis at the point of penetra- tion of the zoospores, but is not found in all. Fig. 194. Chhrochytrium lemnae K.\ehs. Cells in the tissues of Lemna. X 500. (After Klebs.) 167 (i66) Chromatophore dense, with many starch grains: membrane lamel- late . Endosphaera Klebs. Cells spherical or irregular, found in the tissue of water plants. In reproduction internal divisions occur, giving rise to eight or sixteen oval isogametes with two cilia and a pyrenoid. The zygospore pene- trates into the intercellular spaces of Fatamogeton if it is present, but ^''^ C dies if it cannot be found. In the spring time it is
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