278 



CLASS: MASTIGOPHORA 



as in Volvox (Fig. 129). Included in the order ( = Phytomonadina Bloch- 

 man, 1895), amongst other genera, are Chlafnydomonas (Fig. 130), Hmmato- 

 coccus (Fig. 131), Polytoma (Fig. 42), Parapolytoma (Fig. 31), and colonial 

 forms like Gonium (Fig. 132), Pandorina, and Volvox. 



In the sub-class Zoomastigina are found numerous free-living forms as 

 well as the various parasitic or saprophytic flagellates which occur in man 



Fig. 127. — Astasia ienax 



(X 650). (After Stein, 1878.) 



Two individuals, showing changes 

 in form due to peristaltic waves 

 of contraction; each possesses 

 a nucleus, two flagella, and 

 oesophagus, at base of which is 

 a contractile vacuole. 



Par 



Fig. 128. — Fhacus lotigicandus (A) ( x 650) and 

 Euglena oxyuris (B) ( x 450). (From Doflein, 

 1916, after Stein.) 



Par, Paramylum; P, pyrenoid; N, nucleus; T', contractile 

 vacuole; st, stigma. 



and animals. The sub-class is usually divided into several orders as 

 follows: Order Protomonadina, including simple forms with few flagella; 

 the Polymastigina, more complex forms with several flagella and possibly 

 other organs; the Hypermastigina, forms which are mostly parasitic in 



