March, 1908.] 
On the Cytology of Synchytrium. 
283 
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Explanation op Plates XIX and XX. 
The figures were made with a Spencer 1.5 mm. achromatic, oil immer¬ 
sion objective and a Zeis compensating ocular 12 giving at the table a 
measured magnification of approxirr.nately 4000 diameters. They were 
reduced to 2-3 of their original size exactly canceling the enlargement due 
to the camera and rendering the figures the same size as they were seen in 
the field of the microscope, namely enlarged 2670 times. All are camera 
drawings. 
Fig. 1. Early anaphase; a blob of chromatin at one pole, at the other 
4 chromosomes, one covering another. 
Fig. 2. Telophase considerably later than fig. 1.Showing the pro¬ 
cess of transformation of the chromosomes and also the beginning of the 
nuclear vacuole which is without a membrane. 
Fig. 3. Nucleus in wich the rays are beginning to be associated with 
the edges of the nuclear vacuole. 
Fig. 4. Nucleus with two asters the ra\*s of each of which are begin¬ 
ning to form the nuclear membrane. 
