164 



THE MASTIGOPHORA 



mastigoda), and possibly also with the Heliozoa (Dimorpha). They 

 are colourless Flagellata with one to an indefinite number of flagella, 

 a simple vacuole system, and usually a single nucleus. Their 

 nutrition may be holozoic, parasitic, or saprophytic, but probably 

 never holophytic. 



TRIBE 1. PANTOSTOMATINA, Seiin. 



Solid food may be ingested at all points in an amoeboid fashion. 

 SUB-TRIBE 1. HOLOMASTIGODA, Lauterborn. With polyaxonic body, 

 flagella scattered all over the surface, pseudopodial ingestion of food, loco- 

 motion rotatory, defaecation at all points. 



Multicilia, Cienkowski ; M. marina, Cienk., with one nucleus ; M. 

 lacustris, Lauterborn, plurinuclear, the only instance of the kind among 

 Mastigophora. The genus Grassia, Fisch., closely allied to Alulticilia, is 

 found in the alimentary canal of the frog and in the blood of Hyla. 



SUB-TRIBE 2. RHIZOMASTIGODA, F. E.Schultze. With one or two flagella, 

 iiatant and amoeboid or heliozooid phases. The flagella persist through 

 the amoeboid or heliozooid phase. The monomastigote and dimastigote 

 genera present a parallel series, and in addition there is an aberrant genus, 

 Pteridomonas, Penard, in which there is a circlet of 8-12 cilia, which can 

 be rolled inwards like a watch-spring and then bent outwards, exerting a 

 jerking action by which the animal hops backwards. 

 These cilia surround the base of the single main 

 flagellum. 



In the genus Mastigamoeba the flagellum arises 

 directly from the nucleus. The genus Mastigina 

 (Frenzel) is closely related to Mastigamoeba, but the 

 body is covered with a thick pellicle. The position 

 of Mastigella, Frenzel (Fig. 4), is more difficult to 

 determine, as there may be one or more flagella 

 which are quite independent of the nucleus. In 

 Mastigamoeba schulzei (Frenzel) and Mastigina setosa 

 (Qoldschmidt) the body is thickly beset with long 

 rigid bristles which have the general appearance 

 of cilia, but seem to have the fame nature as the 

 adhesive granules (Klebkorner) with which the 

 pellicle and superficial ectoplasm of several species 

 of the three genera are provided. It is possible 

 that they are of the same nature as the spicules 

 of the ectoplasm found in several of the Lobosa 

 (Trichosphaerium, etc.) and some of the Heliozoa 

 (Heterophrys) (cf. pp. 23, 68). 



cv. 



Fio. 4. 



Mastigdla vitrea, Gold- 

 achmidt. OneoftheEhizo- 

 mastigoda. Active form. 

 c.v, contractile vacuole ; 

 /, portions of filamentous 

 algae ingested as food ; ft, 



The life -history of Mastigella vitrina has 

 (Aaer recent iy b een f u iiy investigated by Gold- 

 schmidt (4). During the vegetative life of 

 this anima-l a series of binary fissions occur which are preceded 

 by a withdrawal of the pseudopodia and flagellum and a mitotic 



