1919] Boeck: Studies on Giardia Microti 123 



differed from that of the chromatin of the nuclei, that their consti- 

 tution was aeidophyllic. Some of the very preparations which when 

 stained with basic fuchsin revealed no parabasals were subsequently 

 treated with iron haematoxylin and the parabasals reappeared ; they 

 had been present but the basic fuchsin did not stain them. 



Alexeieff's (1917) work with flagellates, especially Trichomonas 

 aiigusta, has shown that the parabasal rod is of mitochondrial con- 

 stitution. Instead of the rod, in times of division there may be a row 

 of mitochondrial granules which he believes form the parabasal rod 

 by forming chondriomites. He has also shown that the mitochondria 

 are structures which secrete glycogen, which is utilized by the motor 

 and metabolic activity of the organism. 



When preparations of free flagellates killed in Schaudinn's fluid 

 and fixed in ninety-five per cent alcohol were treated with Lugol's 

 solution to test for glycogen in the parabasal bodies two distinct 

 conditions of the parabasal-plasm w^ere noted. The parabasal bodies 

 themselves did not appear but only the glycogen contained in the 

 parabasal-plasm. In the first place the glycogen was seen as a rec- 

 tangular, mahogany colored mass filling all the parabasal-plasm for no 

 membrane-like structure could be detected ; or the glycogen assumed a 

 thin rod-shaped mass, or was in two smaller masses. In the latter two 

 cases, however, these glycogen masses were lying the parabasal-plasm, 

 which was easily identified by the more darkly stained, ovoid, mem- 

 brane-like structure which surrounded them. In the second place, other 

 individuals did not show any glycogen present in the parabasal-plasm, 

 but the area itself was clearly seen as a refractive, rectangular body 

 lying in a position identical with that occupied by the parabasal bodies. 

 The cases which revealed no glycogen in the parabasal-plasm were 

 about the same in number as those that showed glycogen present. Out 

 of fifty flagellates, twenty-three showed glycogen present, twenty-four 

 showed the absence of the glycogen, and three flagellates showed no 

 glycogen or parabasal-plasm present. These three casese Avere inter- 

 preted to mean the complete absence of the parabasal bodies and 

 parabasal-plasm. 



It was thought at the time that perhaps those flagellates which 

 showed only the parabasal-plasm present actually lacked parabasal 

 bodies. Accordingly some of the preparations treated with Lugol's 

 solution were stained with iron haemotoxylin, and after examining fifty 

 flagellates forty-seven were found to have parabasal bodies and three 

 did not. This was identical with the ratio counted in the preparation 



