180 souRci:s or FAEwa v i\ a \ . i Hh'onioi^is 



In endamoebae taken from their natural habitat gly- 

 cogen appears abundantly only in the immature cysts. 

 This is somewhat surprising since the precystic forms 

 seem not to feed. It is possible that large amounts of 

 carbohydrate have previously been stored in a form not 

 demonstrable with the conventional staining methods for 

 polysaccharides. Equally surprising and as yet unex- 

 plained is the rapid disappearance of these glycogen vacu- 

 oles in mature cysts. Future investigations may reveal a 

 high rate of carbohydrate fermentation during the matur- 

 ation process. 



A considerable polysaccharide storage has been re- 

 ported for Coccidia and for Gregarines (Brault and Loe- 

 per, 1904b; Giovannola, 1934; Joyet-Lavergne, 1926; 

 Edgar, Herrik and Eraser, 1944), but it has not yet been 

 demonstrated that these carbohydrates are consumed un- 

 der anaerobic conditions. 



M e s o z a . These curious parasites accumulate rath- 

 er considerable glycogen reserves, as evidenced by the 

 morphological observations of Nouvel (1929, 1929a, 1931, 

 1933, 1935). This applies both to the dicyemids and the 

 orthonectids, parasites of cephalopods and of various 

 invertebrates respectively. Nouvel assumes that, in na- 

 ture, glycogen is used up in the anaerobic metabolism of 

 these organisms, or at least of some of their stages. Un- 

 der experimentally induced anoxic conditions the infu- 

 soriform stages of dicyemids are able to swim around 

 only as long as their glycogen reserve lasts. They can- 

 not withstand an experimental deprivation of oxygen for 

 more than a few hours. As to the vermiform stages, they 

 are still alive after 3 days, but no glycogen consumption 

 could be demonstrated in them by staining methods. 

 Nouvel thinks that during that time a glycogen synthesis 

 even took place, though he assumes that at the same time 

 a glycogen-lactic acid fermentation occurred. He offers 

 no proof from chemical analysis in support of either of 



