WINGE, CYTOLOG. STUDIES IN THE PLASMODIOPHORACE.^. 19 



merontic myxo-amoebae (fig. 11) is seen a granulous plasma 

 of somewhat rounded shape containing nuclei which in the 

 resting-stage are globular, provided with a membrane internal 

 to which is seen a nuclear cavity filled with hyaloplasma, 

 traversed by radial, slightly chromophilous filaments. In 

 the centre of the nucleus is seen a large nucleolus or a 

 caryosome which with the exception of some slightly con- 

 spicuous darker grains (fig. 11, 13, 14) (the idiochromatin?) 

 are formed by a homogeneous substance which appears red 

 when stained with Flemming's Three-Colour Process when 

 Safranin is employed prior to Gentianviolet. — In the fol- 

 lowing will be used the designations idiochromatin and tro- 

 phochromatin as they are used in Maire and Tison's memoir.^ 

 — When the myxo-amoeba nucleus is resting, the chromatin 

 proper, the idiochromatin, which later in the existence of 

 the fungus forms the chromosomes and which, as previously 

 mentioned, is sometimes visible in the caryosome, must be 

 assumed to be partly resolved in the trophochromatin, which 

 latter forms the chromophilous filaments radiating from the 

 caryosome. — 



When the nuclei of an amoeba — always simultaneously 

 and most often with all axes situated in parallel planes — are 

 preparing for division they assume the form of ellipsoids or 

 spindles (fig. 13, 14) and exhibit shght radiation-phenomena 

 at the poles of the spindle. I cannot say for certain that I 

 have ever seen true centrosomes. Then the nucleus again 

 becomes almost round and the caryosome changes its appear- 

 ance (fig. 19, 20). The substance of the caryosome aggregates 

 in the equator of the nucleus while at the same time the 

 polar radiations become more pronounced. At this stage the 

 chromatin often aggregates in 3 — 4 bodies in the equator- 

 plane and may be very similar in appearance to chromosomes. 

 By degrees the polar radiation again decreases in strength, 

 the nucleus once more assumes a short spindle-formed shape 

 almost like a square placed edgewise (fig. 21, 15, 22) and the 

 two kinds of chromatin separate, the vegetative chromatin 

 or trophochromatin placing itself in the centre and the ge- 

 nerative chromatin or idiochromatin lying like a thin equa- 

 torial plate round it. The former appears red when stained 

 with Flemming's Three-Colour Process like the chief mass of 

 the caryosome during the lesting-stage, the latter appears, 



