184 BOTANY 



complex to which he has given the name " kinochromatin." At 

 telophase, dissociation of the two substances takes place once 

 more, and the iron-avid and acidophile materials make their 

 appearance at certain points along the chromosomes as small 

 globules, and these eventually fuse to form fresh nucleoli. Cleland 

 has also brought forward evidence of a similar nature. In 

 CEnothera franciscana sulphur ea he found that the microsporocytes 

 showed nucleoli as rather pale bodies after chromatic material had 

 left them. 



Latter has shown that the nucleolus of Lathyrus odoratus adds 

 chromatic material to the developing chromosomes during pollen 

 formation. The nucleolus here stains deeply, and is more or less 

 spherical in shape. In the peripheral region of the nucleolus 

 there is apparently a greater staining power than in the central 

 region giving the apj^earance of a large central vacuole and a 

 crystal body, which varied in shape, was found within the 

 vacuole. A similar body has been described in CEnothera by 

 Cleland. Occasionally two or even three such bodies were 

 found to be present, but their nature was not ascertained. The 

 suggestion is put forward that they are possibly composed of 

 proteinaceous material. 



In normal nucleoli, after they have assumed an elliptical shape 

 at synizesis and come into contact with the nuclear membrane, the 

 mass of delicate threadwork generally appears to move away from 

 the nucleolus and takes up its position on the side opposite to the 

 nuclear cavity. The separation, however, of the knot of thread is 

 never complete, and the nucleolus, which lies flattened against the 

 nuclear membrane, is connected to the compact mass of thread by 

 means of a few delicate strands. The very constant connection of 

 the thread with the nucleolus during the distribution of deep- 

 staining material along it suggests that a transference of chromatin 

 from the nucleolus takes place. 



As the synizetic knot passes away from the nucleolus across the 

 nuclear cavity, only a single crystalline structure can be seen 

 and one or more loops of the thread remain definitely in contact 

 with the nucleolus, the apex of at least one loop being 

 directed towards this structure. Prolonged examination, however, 



