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Transactions of the Society. 
According to Carlier this process is seen most clearly in the 
cells of the stomach glands, but it occurs also in cells of the glands 
lining the alimentary canal, in salivary glands, and in the liver. 
In connexion with these observations, it is interesting to note 
that similar cases of nucleolar extrusions have been described by 
Maximow ( 1 ) in the salivary glands, and by Macallum (4-8) in the 
pancreas, in both of which cases, the extruded plasmosome material 
is believed to be related to the formation of secretory products in 
the cells. 
Wace Carlier regards the nucleolus as “effete material, derived 
in some way from the chromatin during nuclear activity, and from 
the nutrient material taken up by the exhausted nucleus during 
the synthesis of chromatin from it. This effete material being no 
longer available for nuclear activity, and when abundant tending 
to interfere with the proper performance of nuclear functions, is 
removed from the nucleus, either bodily, or after fragmentation, 
and passes into the cytoplasm, in which it ultimately disappears. It 
is not denied that the extruded nucleolar substance may subserve 
some useful purpose, “ but so far as the nucleus itself is concerned 
it is useless and effete, and may even prove a source of danger if 
too long retained.” 
Gustav Mann, who also carried out physiological researches on 
the nucleus, held the view that “ the nuclear chromatin was the 
organ for the transformation of simple into more complex com- 
pounds,” while the “nucleolus is a storehouse for material which has 
been elaborated by the nuclear segments ” (39). Huie (37), one of 
Mann’s pupils, carried out a series of experiments on the nucleus 
in the insectivorous plant Drosera rotundi folia. When the gland 
cells were stimulated by feeding on albumen, the basophil sub- 
stance in the ground cytoplasm became used up and was replaced 
by oxyphil-staining plasma. “ The restoration of the cytoplasm 
was brought about by the nucleus absorbing food material, meta- 
bolizing it, and then excreting it into the cytoplasm.” Preceding 
the restoration of the cytoplasm, the basophil nuclear substance, 
which had become considerably diminished as the result of the 
secretory activity, increased in amount; the nucleolus however was 
very small. When, however, the cytoplasm was restored to its 
“ resting ” condition, the chromatin was reduced in amount, but the 
nucleolus was increased. 
By the administration of antipyretics, nuclear oxidative pro- 
cesses are greatly retarded ; the result in Drosera was to postpone 
the increase of nuclear chromatin which occurs after feeding with 
peptone for from five minutes to thirty hours. 
These results are advanced as evidence in support of Mann’s 
theory of the metabolic functions of the nuclear organs. 
6. Theories as to the Function of the Nucleolus . — Before con- 
cluding this survey of the literature of the nucleolus, a short 
