SEA ANEMONE. 243 



Many marine animals belonging to different groups, e. g. many Radiolaria, 

 many Anthozoa, especially Sea-anemones, some species of Convoluta among 

 Turbellaria are infested with ' yellow cells.' These bodies have a distinct cell 

 membrane, except in the case of the yellow cells of Acanthometridae (Radiolaria), 

 a nucleus, two colouring matters, one of them chlorophyl, which resemble the 

 colouring matters of certain brown algae, and they are capable of living and 

 multiplying after the death and destruction of their hosts. Under the influence of 

 sun-light they exhale oxygen and form starch both when in and when out of their 

 hosts. It appears probable that they are the swarm spores of various olive-green 

 Sea-weeds (Melanospermeae or Fucaceae), rather than a distinct genus of algae 

 (Zooxanthella of ~Qrand.t= Phitozoon of Geddes). Marine sponges, it may be added, 

 are infested by various algae, green, blue, red, or brown. 



The marine Turbellarian Convoluta Schultzii, and several Turbellarians of the 

 fresh water, e. g. Vortex viridis, the Coelenterates Hydra, Spongilla, and many 

 Protozoa, e. g. Rhaphidiophrys viridis, Stentor polymorphus, are of a bright green 

 colour ; and it is a matter of much dispute whether the green chlorophyl bodies 

 (the Zoochlorella of Brandt) do or do not belong to the organisms in question. 



It appears to be certain from Geza Entz's researches that many Infusoria 

 may be either green or colourless; e. g. Stentor polymorphus is the green variety of 

 Stentor Miilleri. Coleps viridis, Ophridium viride, Vorticella chlorostigma stand in 

 a similar relation to Coleps hirtus, Ophridium versatile, Vorticella campanula. In 

 some instances the green variety is tare. The chlorophyl bodies have a cellulose 

 membrane, a nucleus, two contractile vacuoles, paramylum (starch) bodies, and 

 green chlorophyl as an envelope, or in plates. They multiply outside the body 

 of their host after its destruction and appear to belong to different genera of 

 unicellular algae (Palmella, Tetraspora, Glaeocystis, &c.). Under certain conditions 

 they multiply within their host and are digested by it. Miss Sallitt, however, who 

 has examined some of the same Infusoria as Geza Entz, states that the chlorophyl 

 bodies resemble those of Hydra, and consist of a non-nucleate ball of proto- 

 plasm, with a cup-like investment of chlorophyl containing protoplasm. They 

 occur in the endoplasm and increase by division. In Vorticella chlorostigma the 

 chlorophyl is diffused through the protoplasm. If the Volvocina are rightly 

 included among Protozoa, it must be admitted, without reserve, that there are 

 green-coloured animals which are nourished like plants. 



Professor Ray Lankester's researches on Hydra and Spongilla establish clearly 

 the fact that the green bodies of those animals have not the value of cells. They 

 are devoid of nucleus and membrane. The same specimen of Spongilla may be 

 green where fully exposed to light, colourless or flesh-coloured where in shade. 

 But the colourless part turns green on treatment with sulphuric acid exactly as 

 does the colourless plant Neottia, and microscopic examination shows that colourless 

 representatives of the chlorophyl bodies are present. These bodies in Hydra 

 closely resemble the corresponding structures in plants, and appear, like them, 

 to multiply by fission. The ovum, which is the only ectoderm cell in which they 

 are present, is at one time devoid of them. Kleinenberg has traced their origin in 

 it from colourless bodies. Hamann, on the contrary, states that they migrate 

 into it from the endoderm ; but he appears to start from the point of view of 

 their algal nature, and to be, like some other observers, ignorant of the fact that the 



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