1 90 SOURCES OF ENEKdY IX . 1 A I /;/;o />' fOSIS 



mour, 1941). Harniscli (1941), working independently 

 of Gilmour, also found a pronounced glycogen consump- 

 tion of the mealworm larvae deprived of oxygen. His re- 

 sults, however, were too variable to allow the calculation 

 of an average value. 



The papers quoted above are the only ones in which it 

 was proved by direct chemical analysis that a glycogen 

 consumption occurs in insects under anaerobic condi- 

 tions. The same is probably true also of cockroaches ac- 

 cording to the observations of Slater (1927) and of Davis 

 and Slater (1926, 1928). These authors made no glycogen 

 determinations but studied the respiratory metabolism 

 and lactic acid content of aerobically- and anaerobically- 

 kept roaches and came to the conclusion that a glycogen- 

 lactic acid reaction takes place when the animals are de- 

 prived of oxygen. 



(b) STARCH. It was first showu by Dobell and Laidlaw 

 (1926), and later confirmed by numerous authors, that 

 Endamoeba histolytica grows best in culture if it is fed 

 rice starch which it engulfs and digests readily. According 

 to Snyder and Meleney (1943) the addition of starch is 

 absolutely necessary for a successful anaerobic culture 

 of this parasite while some strains can grow without it 

 if oxygen is not excluded from the medium. Westphal 

 (1934) demonstrated that starch is also indispensable 

 for the culture of Eudiplodinium medium, a ciliate para- 

 site of the stomach of cattle, which requires anaerobic 

 conditions when cultured in vitro. 



Many parasitic protozoa, in addition to those mention- 

 ed above, avidly engulf starch granules in ■culture. They 

 will not be enumerated here since the correlation between 

 the use of starch food and the existence of anaerobiosis 

 has not yet been established experimentally. 



It is interesting in this connection to note that, in gen- 

 eral, a diet rich in starch, or in other carbohydrates, ad- 

 ministered to the host, whether vertebrate or inverte- 



