84 BOTANICAL GAZETTE [JULY 
NOTES FOR STUDENTS 
Mitosis.—In a remarkable series of papers on nuclear division, Lawson 
establishes several claims which differ from current notions, and raises several 
questions which should stimulate research. The first paper, dealing with 
synapsis and showing that this is not a contraction phase, has already been 
noted in this journal..5 The principal conclusion of the second paper" is that 
the achromatic figure is not an active factor in mitosis, but merely the passive 
been teported to break down and disappear. Lawson claims that in the living 
cell it does not break down at all. Even if there should be a rupture, the 
karyolymph, coming into contact with the cytoplasm, would immediately 
that no break would appear. However, 
t was formerly reticulate cytoplasm becomes fibrillar, 
resumes the reticulate form. The cones of the multi- 
€ to form a bipolar spindle, but the bipolar spindle is 
eoftension. The spindle in vegetative cells does not 
: : on account of the vacuolate cyto lasm, pollen 
mother cells being Practically free from vacuoles, see 
*s Bor. Gaz. 51:313. rgrr, 
* Lawson, A. 
. +» Nuclear re) i . aa 
Edinb : , SMOsis as a fact SOE. 
urgh 48: 137-150. ls. 1=4. roxy. ctor in mitosis. Trans. Roy 
“oT 
