iiOO 



PROTOZOA. 



Class II. Flagellata (Mastigophora). 



In many RLizojioda, as described in the foregoing pages, the 

 psendopodia disai:)23ear from time to time and are rephiced by one 

 or two flagelLa ; others ]iave, besides psendopodia, permanent 

 flagella for locomotion and taking of food. Such flagellate spores 

 and flagellate Khizopods form the transition to the Mastigophora, 

 wliich are permanently flagellate, the flagella serving as organs of 

 locomotion and feeding. There are three orders which must be 

 described separately. 



Order I. Autoflagellata. 



All autoflagellates at first sight are closely similar, a usuallr 

 oval body with a vesicular nucleus at one end. a contractile vacuole 

 at the other. At the anterior end there is ofteii added a small red 

 or brown pigment s]3ot (fig. 134), apiparently for the recognition 

 of light, and hence a primitive eye. At this same pole are also 

 one or two flagella ; when a greater number occur they are scat- 



Fio. 134. 



Fio. ];i5. 



Fh;. 13H. 



Fig. ]34.-EH(/?c»f( rirkUs. (After Stein.) <■, conti-.ictilo vacuole: ii, nucleus; o, pig- 

 ment spot. 



F'lr;. 135.-7)/n.)/.j7/,m sirtvlaria. (After Stein.) ,i. :i parasitic rianellate often found in 

 the loriea : /i, contractile vacuole; n, nucleus. 



Fia. Kli.—Cniinrhnlitliii luiihdhitii iii. (.Vfter Stein.) 



tcreil over the body. The l)ody surfa,ce is frequently naked, and 

 m;iy be capable of amcelioid nioti(.)ns: at other times it is covered 

 with a more or less eviilcnt cuticle. Very common are closed 

 wivelopcs and open gol)lct-sha|)ed eases (loriea^, fio-. 1 ;>.=)), and 

 ;ilso siinjilc or branched ,st;i.]ks (fig. Hid), on which the animals 



