Elementary text-book of zoology, general Elementary text-book of zoology, general part and special part: protozoa to insecta elementarytextbo00clau Year: 1892 198 mation. The buds separate themselves from the membrane and become free as small spores, with nucleus and cylindrical appendage, to assume the Noctiluca form under circumstances which have as yet not been closely observed. According to Cienkowski, conjugation may take place between normal forms as well as between encysted forms. The Noctiluca owe their name to their power of producing light, âa power which they share with numerous se
Elementary text-book of zoology, general Elementary text-book of zoology, general part and special part: protozoa to insecta elementarytextbo00clau Year: 1892 198 mation. The buds separate themselves from the membrane and become free as small spores, with nucleus and cylindrical appendage, to assume the Noctiluca form under circumstances which have as yet not been closely observed. According to Cienkowski, conjugation may take place between normal forms as well as between encysted forms. The Noctiluca owe their name to their power of producing light, âa power which they share with numerous sea animals, such as Medusje, Pyi'osoma, etc. The light proceeds from the peripheral layer of protoplasm. Under certain conditions they rise from the; deep to the surface of the sea in such enor- mous numbers as to cause wide tracts of the sea to give out a reddish light. It is after sunset, and especially in the evening, when the sky is overcast, that we get the beautiful phenomenon of the phosphorescent sea. The species distributed in the North Sea and in the Atlantic Ocean is Noctihica â iiiiliaris. Neaily allied is the Mediterranean Leptodiscus medusoides R. Hertwig. Oi-der 2.âCiliata.* Ciliated Ivfusoria with mouth and anus, sarcode body of complicated structure (with endoplasm and exojjlusni), toith nucleus and paranucleus (nucleolus). Fig. ây.;, a n,,t,. ^hc locomotive cuticular appendages that (after Stein), (seen frou: v,Q most frequently meet with are slender ventral side). TT r, Artoral .,. i ⢠i , .1 1 i p <⢠zone of cilia; c, eontractiie ^il^-'^^ ^^'^''^^ o^^en cover the whole surface of vacuole; N, nucleus; i\'', the body in close rows, and give it a striped paranucleus: ^, anus. mi -i- n ^ appeai-ance. Ihe cilia are usually stronger la the region of the mouth, and are here grouped so as to form an adoral zone of large cilia, which, during swimming, causes a whiil- pool, and conducts the matter which serves as nourishment into
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