212 ANAEROBIC META HOLISM 



presence of lactic acid. Employing the commonly used 

 oxidation method, he found that acetaldehyde was indeed 

 formed. But the time required for the completion of 

 the reaction was considerably longer than if only lactic 

 acid would have been present, and the ratio between the 

 acid formed and the carbon dioxide liberated from bi- 

 carbonate did not correspond to the theoretical value. 

 Other acids must, therefore, have been present which 

 were responsible for these discrepancies. 



Worms. Mixed fermentations have been found in 

 the earthworm, in parasitic nematodes and in cestodes. 



Lesser (1909a, 1910) studied the anaerobic metabolism 

 of the earthworm and reported the production of carbon 

 dioxide and of an organi3 acid which was tentatively iden- 

 tified as valeric acid. These findings were corroborated 

 by Miyajima (1937)^ But a study of Lesser 's data re- 

 veals clearly that not enough fatt}^ acid w^as formed to 

 account for the entire anaerobic glycogen loss. He did 

 not search for lactic acid which, according to Davis and 

 Slater (1928a), accumulates within the tissues of anaero- 

 bically kept earthworms. These investigators are even 

 of the opinion that lactic acid is the only end product of 

 the anaerobic carbohydrate metabolism of the earthworm, 

 and that the appearance of fatty acids in Lesser 's exper- 

 iments was due to bacterial activity. They did not, how- 

 ever, make any quantitative glycogen determinations. It 

 is therefore impossible to judge to what extent their as- 

 sumption is well-founded. 



The mixed fermentations occurring in Ascaris and 

 Parascaris appear to be identical; the same end prod- 

 ucts have been found in both animals under both anaer- 

 obic and aerobic conditions. They have been studied 

 by Weinland (1901, 1904), Flury (1912), Fischer (1924), 

 Waechter (1934), von Brand (1934a), Kriiger (1936), 

 Toryu (1936) and Oesterlin (1937). All these workers 



1. An abstract only of Miyajima's paper could be consulted. 



