Glass 1. Gymnomyxa. Order 1. Rhizopoda, 



87 



division (c/. the Gregarines)^ just as in the Metazoa, fertilisation is 

 succeeded by active cell division. For the conjugation of the 

 Infusoria, see that group. 



Gymnomyxa.. . . . . With pseudopodia. 



Infusoria. Body covered with cilia ) ^„. . , -■■ 



^ ■ -xTiT-A X -T r Without pseudopodia. 



Gregarina. Without cilia . . > r r 



Class 1. Gymnomyxa. {Sarcodina.) 



The numerous forms belonging to this class are all possessed of 

 the power of protruding pseudopodia, by means of which they 

 move about, and ingest their food. Most of them are provided with 

 a skeleton, harder portions within or around the protoplasm, varying 

 in form and in chemical composition. They are for the most part 

 marine. 



Order 1. Rhizopoda. 



In some Rhizopoda, for instance, in the Amoeba, which has 

 already been mentioned, there is no skeleton. Most of them, however, 

 are furnished with a protective structure in the form of a shell, 

 which surrounds the greater part of the body. In the simplest cases 

 the shell is cap-shaped, with a single large opening through which 

 the protoplasm projects. In others it is complicated by being 





/■ 





AX-;v 



v^ 



Pig. 47. A {Difflugiaj and B {Euglypha), two imperforate fresh-water Ehizopods, with 

 ohitinoua shells ; in A small foreign bodies are fastened to the shell, n niicleijs, p pseudo- 

 podia. C Marine Ehizopod [Rotalia). — A after Stein, B after Hertwig and Leaser, C after 

 M. Sohnltze. 



