Relation to the Nticleolus in Galtonis candicans , Decsne. 499 
Walker and Tozer (19) have made further investigations into the 
nucleolar budding in the vegetative cells of animals and plants. The 
buds pass out of the nucleus into the cytoplasm. While in the nucleus 
they take a basic stain, but arrived in the cytoplasm their staining reaction 
gradually alters, until they take the acid stain more deeply than the 
surrounding cytoplasm. In the formation of the chromatic bodies from 
the nucleolar buds in Galtonia the staining reaction is reversed. 
Chamberlain (4), in the body cells of Dioon edule , has described ‘ black 
granules’ in the cytoplasm. He believes that they have come from the 
nucleus and have passed through the nuclear wall without becoming 
soluble. The black granules increase in size by imbibing liquid, until 
the granule becomes a thin pellicle enclosing a liquid. ‘ As the pellicle 
stretches, granules pass through it into the watery interior, and the colour 
with iron alum hematoxylin gradually changes from black to gray .’ 1 
There is a suggestive similarity between the above-mentioned cases 
of the extrusion of nuclear material in the higher animals and plants 
and the c chromidia ’ of the lowly forms. A vast literature has accumulated 
round the subject of chromidia. Richard Hertwig (7 and 8 ) was one of 
the first to insist on the importance of the chromidia and introduced the 
terms ‘chromidia’ and ‘chromidial net’. The chromidia are believed to 
be always extruded from the nucleus, and are composed partly of nucleolar, 
and partly of chromatic substances. They may be scattered in the cyto- 
plasm or arranged in a net-like system. Often, as in Arcella vtdgaris , 
each chromidial aggregation forms a new nucleus. Comes (5) has shown 
in Gregarines that the chromidial apparatus varies according to the 
amount of nutrition absorbed by the animal. In the summer, when 
well nourished, the chromidia are most abundant, whilst in the winter, 
when food is scarce, there are very few to be found. 
Hartmann and Prowazek ( 6 ) have recently confirmed Schaudinn’s (14) 
work on the Trypanosome, Haemoprotens noctuae . Before the animal 
encysts the large nucleus sheds out a portion of its karyosome and this 
becomes the second nucleus. Both nuclei send off two small nuclear 
buds which degenerate. The two large nuclei then retreat to the centre 
of the cell and fuse. 
In 1899 Siedlecki (15) observed an elimination of nuclear substance 
in the Sporozoa , and this has since been corroborated by several writers. 
At the formation of the macrogametes the karyosome divides into small 
portions. These go to the periphery of the cell and become surrounded 
by chromatin. The edge of the Coccidium cell is seen to be studded with 
1 i Nuclear gemmation ’ and 1 fragmentation ’ have been found to take place in the fungus 
Synchyirium . The karyosome of the parent-nucleus buds or fragments, and each portion becomes 
a new nucleus. Griggs, R. F. : Some Aspects of Amitosis in Synchytrium. Eot. Gaz., xlvii, Feb., 
1909 , PP- 1 2 7-38. 
