II 



PHYLUM PROTOZOA 



65 



numerous non-nucleated protoplasmic bodies or chromatophores, containing 

 chlorophyll and a green or brown colouring matter in varying proportions. 

 There are also a number of minute rounded bodies of a bluish tint probably com- 

 posed of reserve food-materials. In the young condition (a) the resting cells are 

 globular and microscopic, lying enclosed within the cells of the Sphagnum, but 

 as they grow in this confined space they become elongated and irregular, and 

 tinally burst through the wall of the moss-cell, forming masses (b, c) quite visible 

 to the naked eye. These may bud (C) or undergo binary fission (I)) ; or the 

 protoplasm, retreating from the cell- wall, may divide into numerous small 

 uninucleated amoeboid masses, each of which subsequently surrounds itself with 

 a new cell-wall (E). 



During the whole of the resting stage there is nothing to distinguish Chlamy- 

 domyxa from a plant, and it would certainly be placed among the lower Algas 

 if the active phase of its existence were unknown. 



In the active stage (A) the protoplasm protrudes from the ruptured cell-wall 

 in the form of stiff pseudopods produced into a complex network of extremely 

 delicate filaments, which are much branched and perhaps anastomose, and may 

 imite to form larger masses of protoplasm at a considerable distance from the 

 original cell. At the same time the bluish spheres (-sp. ) found in the resting 

 stage take on a spindle shape and travel slowly along the filaments. 



In one of the two known species the protoplasm entirely leaves the cyst wall 

 and becomes free in the water. 



The filaments are used to capture living organisms (/. ) which are digested by 

 the protoplasm surrounding them, the products of nutrition being conveyed 

 along the network to all parts of the organism. Thus in the active condition the 

 nutrition of Chlamydomyxa is holozoic, i.e. strictly like that of an animal, the 

 food consisting of living protoplasm. In the resting stage, on the other hand, 

 nutrition is purely holophytic, i.e. like that of an ordinary green plant, the food 



B 



rtu. 



Fio. -Hi. "Labyrinthula vitellina. A, specimen crawling on a fragment of Alga (a.) ; c. ceils 

 travelling in the filaments. B, part of specimen in resting condition with heap of cells (c.) ; 

 C, a single cell from an actively moving specimen with connecting threads ; nn. nucleus. 

 (From Biitschli's Protozoa, after Gienkowsky.) 



consisting of the carbon dioxide and various mineral salts dissolved in the water. 

 Chlamydomyxa multiplies in the resting condition by the formation of spores 

 each containing two nuclei. These give rise to flagellulse, the further history of 

 which has not been traced. 



Labyrinthula (Fig. 49) in the resting stage (B) consists of a heap of small 



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