134 



CYTOPLASMIC INCLUSIONS 



The composition of the segregation bodies is as varied as their 

 morphology and results from the same causes — changes in the environ- 

 ment. Under natural conditions they may contain proteins (Millon's 

 reaction), glycoproteins (Fischer's reaction), cholesterin (Schultz re- 

 action, digitonin reaction), or be stained with bile pigments. The 

 alveolar type of course contains mostly water. The segregation granules 

 will store basic dyes in salt solution, acid dyes in the presence of pro- 

 teins, silver in the form of kollargol or other similar compounds, iron 

 albuminates, cholesterin, and so forth. According to the "ferment theory 

 of the vacuome" of Kedrowsky (1932b), enzymes are present in the 



Figures 36-37. Segregation granules in Trypanosoma diemyctyli, neutral red stain. 

 (After Nigrelli, 1929.) Figure 36. Preformed granules around the blepharoplast; Figure 

 37, preformed granules and granules induced by prolonged exposure to neutral red. 



segregation bodies, but, as is the case with the digestive granules, no 

 direct proof of this is available. 



The segregation bodies obviously function in the concentration and 

 storage of various materials, particularly proteins. This may be accounted 

 for on a purely physical basis, as, for instance, the tendency of basic 

 dyes to migrate to a more acid region, or the tendency of molecules to 

 migrate toward bodies of opposite charge. The exact mechanism is, of 

 course, a complex problem and cannot be taken up here, but the es- 

 sential point at present is that the granules may play a purely passive 

 role — the accumulation and storage of materials which originate else- 

 where. 



Accumulation is merely one part of the function, according to the 

 enzyme hypothesis of the segregation granules, advanced at nearly the 

 same time in slightly varying forms by Koehring (1930), Kedrowsky 

 (1931 on), and Volkonsky (1929 on). Koehring based her conclu- 

 sions on the supposed specificity of the neutral red reaction for proteo- 

 lytic enzymes (see p. 178). Kedrowsky considers that both the synthesis 



