158 AEROBIC FERMENTATIONS 



information that we obtained from Kozancikov's paper is 

 rather fragmentary). That no harm results may be due 

 to the fact that the diapause is only a transitory stage 

 in the life of an insect. Some of the end products may 

 even be utilized for subsequent synthetic processes. 



1. OCCURRENCE OF AEROBIC FERMENTATIONS 



A survey of the invertebrate phyla shows that the oc- 

 currence of aerobic fermentations is somewhat erratic. 



It was reported in all major groups of protozoa, both 

 fre3-living forms and parasites, with the exception of the 

 rhizopods. In general, it has been revealed by the fact 

 that the pH, or the alkaline reserve of the medium in 

 which the organisms were kept, decreased or that carbon 

 dioxide was liberated from bicarbonate. A direct iden- 

 tification of the end products was undertaken in only very 

 few cases. It is clear that, with indirect methods, many 

 cases may have escaped detection. Loefer (1936) points 

 out that this failure to find, by pH determination, an acid 

 fermentation of carbohydrates in Paramaecium bursaria 

 may be due to a neutralization of acids by concomitantly 

 formed bases, perhaps ammonia. The occurrence of 

 aerobi3 fermentation has been ^definitely proven in the 

 following cases: in many species of Trypanosoma (von 

 Fenyvessy, 1926; von Fenyvessy and Reiner, 1928; Klig- 

 ler and Geiger, 1928 ; Kligler, Geiger and Comaroff, 1929 ; 

 Geiger, Kligler and Comarotf, 1930; von Brand, Regen- 

 danz and Weise, 1932 ; Reiner and Smythe, 1934 ; Reiner, 

 Smythe and Pedlow, 1936), in various species of LeisJi- 

 mania (Colas-Belcour and Lwoff, 1925; Noguchi, 1926; 

 Salle and Schmidt, 1928; Salle, 1931), in Leptomonas and 

 some species of Strigomonas (Colas-Belcour and Lwoff, 

 1925; Lwoff, 1934), in EutricJiomastix (Cailleau, 1937), 

 in some species of Trichomonas (Witte, 1933; Cailleau, 

 1934, 1936, 1937; Riedmiiller, 1936; Andrews and von 

 Brand, 1938; Trussell and Johnson, 1941; Plastridge, 



