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J. Ramsbottom, 
migrates through the nuclear membrane, forms a vacuole and a membrane 
about itself, and becomes an independent small nucleus, the process being 
repeated until the parent nucleus is converted into small nuclei often 
forming a definite group and 2. “Heteroschizis” where the membrane of 
the parent nucleus dissolves and the karyosome fragments into a number 
of pieces each of which becomes a new nucleus. 
Bally (1911) has published his results in Synchytrium Taraxaci. 
The primary nucleus in the young stages possesses a large nucleolus rich 
in chromatin. Later, secondary nucleoli arise from this and can pass out 
of the nucleus to become the bases of secondary nuclei. The process 
recalls that of nuclear gemmation. Indirect division of the primary nucleus 
was not observed. The secondary nuclei divide indirectly. They differ 
from the primary nucleus principally in possessing a greater number of 
secondary nucleoli and better developed linin threads. The division stages 
seem to agree with those found by previous observers. The nucleolus 
remains outside the nuclear membrane. The telophase does not show the 
karyodermatoblast present in S. decipiens and S. Puerariae. Also the 
spindle instead of being drawn into the daughter nuclei persists for a 
time in the cytoplasm and then dissolves. After the segmentation of the 
cyst there is a different type of division. Here the nucleolus, instead of 
persisting, is used up in the formation of chromosomes and the intra¬ 
nuclear fibres. In both types of division four chromosomes are present 
a low number being apparently the rule in the genus. In the sorus 
before segmentation, all the nuclear divisions are simultaneous: after 
cleavage, they are simultaneous in each sporangium but without any 
reference to neighbouring sporangia. 
Chrysophlyctis endobiotica was also studied and most of Percival’s 
(1910) results confirmed. Unlike the latter he does not regard the fungus 
as a species of Synchytrium . The uniciliate swarm spores possess a pair 
of small chromatin particles. The youngest parasitic stages, however, 
show a pronounced nucleus with a very large nucleolus but a very small 
quantity of dense cytoplasm. A nuclear membrane, not observed by 
Peecival, is present. From these arise either sporangial sori or resting 
sporangia. In the resting sporangia no mitotic divisions of the primary 
nucleus were seen. Percival s account of the origin of the zoospores is 
confirmed. The nucleus by a method of nuclear gemmation sheds chro- 
mitin as chromidia into the surrounding cytoplasm which pass unchanged 
into the zoospores. The primary nucleus remains undivided during this 
process. Its nuclear membrane dissolves finally and the remains of the 
nucleolus etc. are found amongst the swarmers. According to Percival 
the nuclei in the sporangial sori divide by mitosis, the spindle being 
intranuclear and the nucleolus disappearing. Bally did not see this 
division: neither could the differences in the structure of the nuclei in 
the two types of spores, recorded by Percival, be substantiated. The 
transitions to sporangial sori are represented by multinuclear stages with 
nuclei of different sizes. Chrysophlyctis thus differs from Synchytrium 
in the manner of zoospore formation, in the resting sporangia, and, 
further, in the manner of penetration into deeper lying tissues. 
A third species investigated was Urophlyctis Rubsaameni. Schröter 
and Magnus held that in this genus there is sexual reproduction; two 
vesicles copulate one of which empties its contents into the other. 
