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HANDBOOK OF PROTOZOOLOGY 



Genus Octomitus Prowazek. Similar to Hexamitus, but 

 parasitic. Body plastic; no cytostome; nutrition parasitic. 



Octomitus intestinalis (Dujardin) (Fig. 62, h, c). About 10 

 to 16 microns long. In the intestine of the frog, also in midgut 

 of Trutta fario and in the rectum of Motella tricirrata and M. 

 mustela in European waters. Moore noted a similar form in 

 young salmon and trout in North America, and named it 

 Octomitus salmonis. 



Octomitus periplanetae Belaf. In the gut of the cockroach. 



Fig. 62 a. Hexamitus inflatus. X520 (After Klebs). 



b, c. Octomitus intestinalis. X 1200 (After Alexeieff). 



d-f. Giardia intestinalis. X800 (After Kofoid and Swezy). 



d, front view; e, profile; f, cyst, 

 g. Trepomonas agilis. X800 (After Klebs). 

 h. Gyromonas ambulans. X400 (After Seligo). 

 i. Trigonomonas compressa, feeding on a Bacillus. 



X370 (After Klebs). 

 j. Urophagus rostratus. X600 (After Klebs). 



Genus Giardia Klinstler ( = Lamblia Blanchard). Pyriform; 

 bilaterally symmetrical. In profile, dorsal side convex; the 

 ventral side possesses a single sucking disc at the anterior re- 

 gion. Eight fiagella: four from the margin of the sucking disc; 



