472 BOTANICAL GAZETTE * ” [JUNE 
The second male cell comes in contact with the upper polar nucleus, while 
the lower polar nucleus comes in contact with the male cell and upper polar 
nucleus and the three fuse simultaneously. The endosperm nucleus divides 
before the oospore shows signs of division. Only in Naias, as reported by 
Guignard, does the oospore divide first, but even here, when division of the 
endosperm begins, it proceeds with much greater rapidity than in the embryo. 
The two deeply staining bodies reported by the reviewer in the end of the 
pollen tubes of Silphium and Erigeron were observed and figured in Mono- 
tropa, but their origin was not determined. The article is illustrated with 
ten excellent figures. — W. J. G. LAnp. 
Haupt * adds somewhat to our knowledge of gland action by a recent 
paper from the Leipzig laboratory. Working with extrafloral nectaries, he 
finds that the secretion of sugar begins at a certain age of the nectary and 
with relatively high atmospheric humidity, ¢. ¢., with checked transpiration. 
After it is started, a rise in humidity increases the amount of water excretion, 
but that of sugar remains constant. Usually when secretion is stopped, the 
already secreted sugar fails to be resorbed, but in some cases resorption 
occurs. In Vicia and certain Euphorbiaceae the red and yellow rays of the 
sun’s ssi are a for the secretion of sugar, and the secretion is 
resorbed i nd violet light. Plants deprived of CO, exhibit 
m the light reaction ven after many days; thus the response is not connected 
the photosynthetic ‘process. There exists in all plants experimented 
nimum temperature for the beginning of secretion, but after the 
og a even somewhat below this minimum.— 
w of three or four megaspores, the lowest of 
It! raed one of the middle cells occasionally 
— po e above and below. In Fatsia Japonica a 
- - middle cell of an axial row of three had divided 
se, after the mother cell had divided transversely, 
a ‘very 
chanik der extrafforalen Nektarien. Flore 90: 
| inthe ‘opinion of the writer strengthens the - 
ie cae eile 
co a Sci. in Bot. 
