CYTOPLASMIC INCLUSIONS 155 



The formation of paraglycogen bodies has been followed in only a 

 few cases. The bodies of Peloniyxa behave like permanent bodies with a 

 protein stroma and with the paraglycogen being built up or released as 

 the case demands (Leiner, 1924). The paraglycogen granules of Poly- 

 plastron are likewise independent of other formed components and are 

 apparently self-perpetuating (Fig. 56), since they show regular division 

 (MacLennan, 1934). The dense centers may be naked or, more often, 

 surrounded by an envelope of varying thickness. In the largest of these 

 compound granules, the centers are dumb-bell-shaped or double, and 

 in the latter the envelope also is constricted. These stages probably repre- 

 sent growth or utilization stages and division stages, although this was 

 not confirmed by following a single granule in live ciliates. The com- 

 plex granules of Amoeba hydroxena (Fig. 58, 59), in which a varying 

 number of glycogen granules are imbedded in glycoproteid (Wermel, 

 1925), suggests a conversion of glycogen into glycoprotein for storage 

 and the reversal of this process in utilization. 



Some paraglycogen granules are formed in association with mito- 

 chondria instead of being independent bodies. The paraglycogen in 

 Ichthyophthirius first appears as a minute vacuole (Fig. 17) in the center 

 of a sphere of mitochondrial material (MacLennan, 1936) . As the gran- 

 ules grow, this mitochondrial shell breaks into short rods fused to the 

 surface of the paraglycogen. The mitochondria disappear after the gran- 

 ule has attained full size. Joyet-Lavergne ( 1926b) also noticed a morpho- 

 logical relationship between mitochondria and paraglycogen of greg- 

 arines, but says "il y a la un simple rapport de contact et nous n'avons 

 aucune raison de suppose une intervention dans da genese du para- 

 glycogene." However, in the case of a granule in the center of an un- 

 broken sphere, as in Ichthyophthirius, it is difficult to list the relationship 

 as merely an incidental contact. 



Duboscq and Grasse (1933) show that the glycogen granules of 

 Cryptobia helicis are not found scattered in the cytoplasm, but are formed 

 in close contact with or in the strands of the parabasal bodies (Fig. 65 ) . 

 The glycogen is not laid down in the summer, but only in the winter, a 

 fact which, they point out, would explain the negative results of other 

 authors. This formation of glycogen by the parabasal body parallels the 

 secretion of protein granules by the macronucleus of ciliates — a part of 

 the segregation function which, in most species, is performed by isolated 



