1897 | ABSTRACTS OF BOTANICAL PAPERS Igt 
ditions their protoplasm with much constancy gives results which 
depend on the nature of the solution used, and stand in direct 
relation to its chemical composition. 
CHARLES PorTER Hart: Js the characteristic acridity of certaiu 
species of the arum family a mechanical or a physiological property or 
effect ?— Preparations of the extracted juice of arum that have 
been filtered still preserve their acridity and produce remarkable 
physiological effects. 
W. J. Beat: How plants flee from their enemies—I\t is found 
impossible in many cases to maintain beds of a given species for 
any considerable length of time in the place where they were 
originally set on account of various enemies from which the 
plants either slowly or rapidly withdraw. Water plants also 
exhibit peculiar habits in this respect. Marsilia quadrifolia has 
been observed to grow at different levels and in different ways, 
following changed external conditions. 
ALEX. P. ANDERSON: Stomata on the bud scales of Abies pecti- 
nata.— Heretofore stomata have been thought never to occur on 
the bud scales of gymnosperms. They are now found on those 
of the species named. 
LEX. P. ANDERSON: Comparative anatomy of the normal and 
diseased organs of Abies balsamea affected with Aicidium elatinum. 
—Comparison shows differences in structure of leaves of the 
lateral and erect branches; the presence of two to six resin 
canals in the diseased bud scales, from which the resin, exuding 
through fringing hairs, spreads in a layer I to 3™™ thick over 
the scale; and the formation of resin vesicles in the primary 
cortex by the growth of the epithelial lining to the resin canals. 
ALEX. P. ANDERSON: On a new and improved self-registering 
balance. 
Cuartes O. Townsenp: The correlation of growth under the 
influence of injuries.—The purpose of the experiments conducted 
by the writer was to determine in what time, through what dis- 
tance, and to what extent an injury inflicted upon one part of a 
plant will influence the growth of the injured and also of the 
uninjured parts. Seedlings were chiefly employed, but older 
