Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 198 PKOTOZOA. 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, —a power which they share with numerous sea animals, such as Medusae, Pyrosoma, etc.
Elementary text-book of zoology (1884) Elementary text-book of zoology elementarytextbo0101clau Year: 1884 198 PKOTOZOA. 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, —a power which they share with numerous sea animals, such as Medusae, Pyrosoma, etc. The light proceeds from the peripheral layer of protoplasm. Under certain conditions they rise from the depths of the sea to the surface 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 Noctiluca miliaris. Nearly allied is the Mediterranean Leptodiscus medusoides R. Hertwig. vi Order 2.—CILIATA.* Ciliated Infusoria with mouth and anus, sarcode body of complicated structure (with endoplasm and exoplasm), ivith nucleus and paranucleus (nucleolus). . »schia mytu«, The locomotive cuticular appendages that (after stein), (seen from we most frequently meet with are slender ventral side). Wz, Adoral .,. , . , „ , zone of cilia; c, contractile Cllia' wnich often cover the whole surface of vacuole; N, nucleus; N>, the body in close rows, and give it a striped paranucleus; A, anus. appearance. The cilia are usually stronger in the region of the mouth, and are here grouped so as to form an adoral zone of large cilia, which, during swimming, causes a whirl- pool, and conducts the matter which serves as nourishment into the mouth (fig. 137). This adoral zone is more highly developed in fixed Infusoria such as the bell
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