166 BOTANICAL GAZETTE has. 
It has long been known that the inferas} osmotic prewaieal | 
secretion of other solutes into the cell sap has been taken up again by . 
Mayenburg.° That the internal pressure does not rise by mere in : 
sion of the surrounding solute, at least in most cases, was shown by Es ; 
hagen, and the present author (who uses Aspergillus niger) has ¢ 
is an exception to this rule, as might be expected from the great ' 
this substance to penetrate most protoplasts. Fungi grown in cone 
glycerin solutions are found to contain this compound in about the 
concentration as it occurs in the surrounding medium oe 
An attempt was made to determine the nature of the interoall 
substances in the more usual cases, where inward diffusion plays 20 
tant part in the rise of turgor pressure. 
jecrease. 
are ‘second by rise in beteinal osmotic eee E 
lace valuable contributions to our mee of the: 1 
Winkler was also able to corroborate Maas s oben 
nucleate portions of the eggs of the sea urchin, Echinus 
will produce normal embryos after the entrance of sperms. | 
is carried further, however. If a non-nucleate portion be ¢ 
normally fertilized egg, this portion may be made to - 
. embryo by a second fertilization. The experiment no longet 
_€ver, after the first cleavage plane has been formed. __ 
Unfertilized ges of Arbacia pustulosa were made t to ; 
_® MAYENBURG, Orromar HEINsIUs von: Lésungs-conce 
Ae regulation bei den: Schiacielpiisen, Jahrb. wiss. Bot. ape? 381 
* WINK NKLER, Hans: Ueber eho: und Befruchtung- 
36: 153-795. ects oe 
