390 BOTANICAL GAZETTE [wove 
of tissue taken from some suitable plant is placed in the long closed arm of a 
J-tube. The tube is filled with water and the atmospheric pressure is removed 
from the short arm by means of an air-pump. The strip of tissue, in the upper 
part of the column of water held in tension by the weight of the lower parts, 
remains curved showing an osmotic pressure existing in the cells in spite of this 
tension.—H. HAssELBRING. 
CAMPBELL?® has continued his studies of the Araceae by investigating 
Anthurium violaceum leucocarpum and Nephthvtis liberica. The account of 
Anthurium is quite like that of the usual angiosperm. The archesporium in the 
ovule is a single hypodermal cell, which divides periclinally. The primary 
sporogenous cell passes directly into the megaspore without division; and in 
the development of the gametophyte to the fertilization stage there is nothing 
worthy of remark. In the formation of endosperm there is no free nuclear 
division, a wall appearing with the first division, which occurs at the antipodal 
end of the sac, the formation of endosperm thus proceeding from the antipodal 
toward the micropylar end of the sac. The embryo is at first an almost globular 
mass of cells, with a “rudimentary” suspensor. Nephthytis proved to be quite 
variable in the development of the embryo sac. The archesporial cells are vari- 
able in number, and generally more than one embryo sac begins to develop. 
In no case did the mature embryo sac show the usual angiospermous condition, 
and so great was the variation that no condition could be selected as the pre- 
vailing one in the species. Among the most striking forms of mature sacs are 
the following: two nuclei, one at each end; a complete egg apparatus and a 
single antipodal nucleus; three antipodal nuclei and a single micropylar nucleus; 
twelve or thirteen nuclei, the three uppermost fusing; various forms of chambere 
sacs; fusion of contiguous sacs. The general conclusion is reached that the 
Araceae are relatively primitive monocotyledons.—J. M. C. 
Von ScHRENK?7 has given an account of intumescences formed on leaves 
of cauliflowers as a result of chemical stimulation. The plants had been sprayed 
with copper sprays; several days after application the wart-like growths — 
observed on the leaves. By an experimental analysis of the conditions si 
the-intumescences the author finds that they are readily produced by sprays bh 
ammonium copper carbonate and other copper salts, and in some Cs© oo 
ammonia and ammonium carbonate. Soil and atmospheric conditions, incluc- 
ing heat and water supply, had nothing to do with their formation. ss 
It is clear that the peculiar outgrowths of leaves known as intumescences a 
produced by various factors in different plants. Usually they have been epee 
to excessive water in the tissues due to moist atmosphere, coupled with 
photosynthesis. Soraver, Kister, and HaBerLANpT have fo 
26 CAMPBELL, D. H., Studies on the Araceae. III. Annals of Botany 19:329 4 
pls. 14-17. 1905. : : 
27 Von SCHRENK, H., Intumescence formed as a result of chemical stimulation: 
Rept. Mo. Bot. Garden 16:125-148. pls. 25-31. 1905- 
