318 BOTANICAL GAZETTE 
The solution must stand for several weeks in a beaker, covered only by a 
piece of filter paper, before it is ready for use. Then stain for 24 hours 
in a mixture of 10 parts of the above solution in 100 parts of a I per cent. 
aqueous solution of formalin. Wash in running water at least one hour and 
then differentiate in saturated alcoholic solution of picric acid 1 part, water! 
part, and 94 per cent. alcohol 2 parts. The differentiation will generally — 
require only a few seconds. Rinse in 75 per cent. alcohol and examine. lf 
still too deeply stained transfer again to the differentiating solution and 9 
continue until the stain is clear and sharp, then wash in running water for an 
hour, transfer to 50, 75, 94 per cent., and absolute alcohol, clear in tolvol aad 
mount in dammar. 
From such preparations the following conclusions are drawn. The Cen 
tralkérper, or central body of the Cyanophyceae, is a nucleus. The most 
important reason for this conclusion is the behavior of the central 1 body dut- 
ing cell division. In all cells of the Cyanophyceae, except the heterocysts 
the nuclei of which degenerate very early, a single nucleus is pre 
form depending largely upon the shape of the cell. The resting | 
consists of a slightly staining ground mass in which are imbedded name 
_ deeply staining granules. These granules from their behavior duri 
ion, their reaction to stains and digestive fluids, are to be i 
chromatin granules of higher plants. They are not the “ red B' 
a li. The nucleus differs from that of higher plants in not 
‘nucleolus or nuclear membrane. During nuclear division the 
: into chromosomes _— separate as division proceeds. Str 
first appears asa Sie midway between the daughter ~ | 
gs toward the center until the partition is — ee 
‘to be 
7 it. interesting to note that Zacharias, in a lengthy and — 
_ diced review of Hegler’s paper (Bot. Zeit. 59: baie ie - 
a accuracy of these conclusions and insists that th no 
ree —Cuar-Es J. CHAMBERLAIN. 
