Elementary text-book of zoology, general Elementary text-book of zoology, general part and special part: protozoa to insecta elementarytextbo00clau Year: 1892 NOCTILUCA. 197 of the sea, and possesses a peach shaped body which is surrounded by a cuticular envelope, and bears a tentacle-like appendage, A furrow- like invagination is situate at the base of this appendage, at one end of which is the mouth close to a tooth-like prominence and a slender vibratile flagellum. The soft body consists of a central mass of conti-actile protoplasm, connected by fine and anastomosing threads with a layer o
Elementary text-book of zoology, general Elementary text-book of zoology, general part and special part: protozoa to insecta elementarytextbo00clau Year: 1892 NOCTILUCA. 197 of the sea, and possesses a peach shaped body which is surrounded by a cuticular envelope, and bears a tentacle-like appendage, A furrow- like invagination is situate at the base of this appendage, at one end of which is the mouth close to a tooth-like prominence and a slender vibratile flagellum. The soft body consists of a central mass of conti-actile protoplasm, connected by fine and anastomosing threads with a layer of the same substance which lines the cuticular envelope of the body. In the central protoplasm lies a clear body, the nucleus; and the spaces between the radiating processes, which exhibit the phenomena of granule currents, are filled with fluid. The contractile substance extends into the appendage, and there assumes a cross- striped appearance (fig. 136). .—Noctihica miliaria (partly after Cienkowski). N, Nu- cleus, a, Single animal, h, conjugation of two individuals. c and d, swarm spores. The reproduction takes place by means of fission (Brightwell), pre- ceded by division of the nucleus ; or by spore formation (Zoospores). In the latter case, the flagellum is absorbed or thrown off, and the Noctiluca assumes a spheroidal shape. After the disappearance of the nucleus, the sarcode contents accumulate on the inner side of one region of the cuticle, divide into from two to four masses which ai'e not sharply separated from one another, and the cuticular envelope is thrust out into a corresponding munber of protuberances. These buds increase and form numerous wart-like prominences, the future spores. They arise, therefore, at the expense of the protoplasmic contents of the disc, which is gradually exhausted in their for-
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