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DEGENERATION AND DEATH IN ENTAMBA RANARUM. 7138 
the whole process in the amcebe from two toads which I 
recently examined (January, 1909; both animals were from 
the same locality). 
The first stage in the process of degeneration consists in 
an increase in the size of the nucleus, with a well-marked 
peripheral thickening. All stages intermediate between 
those shown in text-fig. A, 1 and text-fig. B were to be found. 
During this process, there does not appear to be any consider- 
able increase in the actual amount of chromatin present in the 
nucleus: for though the degenerate nucleus often attains twice 
TExT-FIG. B. 
E. ranarum, an individual in process of degeneration. n = Nucleus 
F = Food bodies. 
the diameter of the normal nucleus, it nevertheless stains much 
less deeply with chromatin stains (compare text-figs. A, 1 and 
2). The central part is usually almost free from chromatin in 
the degenerating animals (see text-fig. C, 1). During these 
morphological changes in the nucleus, chemical changes also 
take place. A number of refractive granules make their 
appearance in the nucleus (text-fig. A, 2, ete.). These granules 
do not take up the nuclear stain, and are very distinct in the 
living animal. In later stages of degeneration, they are re- 
placed by granules of brown pigment: but whether they are 
directly converted into pigment, or whether the pigment is a 
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