PHYSIOLOGY 



91 



Protozoa 



Enzymes 



Observers 



Aethalium septicum 



Pelomyxa palustris 

 Soil amoebae 



Balantidium coli 

 Glaucoma pyriformis 



Colpidium striatum 



Poly- and Hyper- 

 mastigina in wood 

 roach 



Pepsin-like enzyme, dis- 

 solving albumins in acid 

 medium 



Pepsin-like and diastatic 

 enzymes 



"Amoebodiastase": tryp- 

 sin-like, active in neutral 

 or slightly alkaline me- 

 dium, liquefies gelatin, 

 coagulates albumin, in- 

 active at 60°C. 



Diastatic enzyme 



Proteolytic enzyme, ca- 

 pable of hj^drolyzing 

 casein 



Proteolytic enzyme, ca- 

 pable of hydrolyzing 

 casein 



Cellulase; Cellobiase 



Krukenberg 



(1886) 



Hartog and 



Dixon (1893) 

 Mouton (1902) 



Glaessner (19081 

 Lwoff (1932) 



Elliott (1933) 



Cleveland et al. 

 (1934) 



their contents. Pelomyxa (Stole), Foraminifera (Schaudinn), 

 Amoeba (Rhumbler), Hypermastigina, Polymastigina (Cleve- 

 land), etc., have also been known for possessing the power of 

 cellulose digestion. Many of the Hypermastigina and Polymasti- 

 gina which lead symbiotic life in the intestine of the termite and 

 the wood roach, as demonstrated by Cleveland and his cowork- 

 ers, digest by enzymes the cellulose which the host insect ingests. 

 The assimilation products produced by an enormous number of 

 these flagellates are seemingly sufficient to support the protozoans 

 as well as the host. The ciliate commensals inhabiting the stomach 

 of ruminants also apparently digest the cellulose, since the fecal 

 matter as a rule does not contain this substance. The digestion of 

 fat by Protozoa had not been known, although oils and fat have 

 been observed in numerous Protozoa, until Dawson and Belkin 

 (1928) injected different oils into Amoeba duhia and found that 

 from 1.4 to 8.3 per cent of the injected oil was digested. 



The indigestible residue of the food is extruded from the body. 

 The extrusion may take place at any point on the surface in many 

 Sarcodina by a reverse process of ingestion of food. But in pelli- 



