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1899] STUDIES ON REDUCTION IN PLANTS 3 
preparation in Flemming’s chrom-osmium-acetic solution for 
twenty-four hours. It was then washed in running water from 
twelve to twenty-four hours, dehydrated with grades of alcohol ; 
decolorized by placing for twenty-four hours in bulk in hydrogen 
peroxid and alcohol, made by using 70 parts of a 95 per cent. 
alcohol and 30 parts of hydrogen peroxid. It was then stored 
in 75 per cent. alcohol after one rinsing. Six months later a 
portion of the material was placed in the hands of a student 
(Miss Susie P. Nichols) for study, and three months later the 
remainder was prepared on the slide for study by Mrs. W. A. 
Murrill under my direction. It was imbedded in paraffin, cut 
with a Minot-Zimmermann microtome 6.6—13.3 m thick, stained, 
some in Flemming’s triple safranin-gentian-violet-orange stain, 
and some with iron hematoxylin. For the present description 
of the material, and for the conclusions presented, the writer 
alone is responsible. 
During the formation of the spirem the linin network gradu- 
ally disappears, and a more or less continuous thread is formed. 
A distinct spirem was not observed, though this phase of mitosis 
has not yet been sufficiently studied. Even at the time of the 
longitudinal cleavage of the thread it was seen to anastomose 
more or less, where, in its windings, portions came in contact. 
At this time it presents the appearance of a very open, irregular 
network. The chromatin granules, at first distributed over the 
linin network, gradually accumulate in small masses scattered 
along the thread. As the spirem thread becomes more distinct 
it shortens, and accompanying this the small masses of chro- 
matin increase in size, giving an appearance of a string of beads, 
or they present an irregular moniliform appearance. Inaddition 
to this beaded appearance of the thread the masses of chromatin 
are more or less irregular or angular. At some of the angles of 
the chromatin masses short delicate threads are attached, prob- 
ably remnants of the linin reticulum which do not participate in 
the formation of the spirem. This, with the angularities of the 
chromatin masses, gives a somewhat ragged contour to the 
spirem. Quite early in the formation of the spirem, and before 
