1905] CURRENT LITERATURE 391 
certain cases due to the action of different poisons, and von ScHRENK adds 
another clearly defined case due to action of specific chemical stimuli. In this 
connection it is interesting to note that almost simultaneously with voN SCHRENK, 
Sremmer?® has described intumescences on Ruellia formosa and Aphilandra 
Porteana which were produced regularly when the plants were transferred to am 
atmosphere of relatively greater humidity, while all attempts to produce them 
on the former plant by means of solutions, including copper sulfate failed. Aphi- 
landra was apparently not subjected to this treatment—H. HAssELBRING. 
THE microspores of Araucaria Bidwillii are described in a preliminary 
paper by Lopriore.?9 The intine and exine are clearly differentiated, the intine 
being about twice as thick as the exine. ‘The numerous large starch grains make 
it rather difficult to get a clear view of the internal structures. The spores get- 
minate best in darkness in a 12 per cent. sugar solution. The pollen tubes reach 
their greatest length—about ten to twenty times the diameter of the pollen grain— 
in eight to ten days. 
At the first division of the pollen mother-cells the number of chromosomes is 
twelve. As the spore germinates, two lens-shaped cells are cut off from the main 
body of the spore. These are not evanescent, but divide and give rise to a mass 
of about fifteen cells. ‘The walls of these cells soon disappear, leaving the nuclei 
free in the general cytoplasm of the spore. Further nuclear division then takes 
place until the spore contains 20-44 nuclei, 36 being the most frequent number. 
There are no divisions after the pollen tube begins to develop. Two nuclei in 
the end of the tube, somewhat larger than the rest, are regarded as vegetative 
nuclei, while the others are regarded as equivalent to spermatozoids. Judging 
from LoprrorE’s figures of the germination of the spore, the reviewer weatarre 
{0 hazard the guess that the two larger nuclei are the male nuclei, while the rest 
of the numerous nuclei result from an unusual development of the prothallial 
region.—C. J. CHAMBERLAIN. 
Henry N. Riwtey,3° director of the Botanic Gardens at Singapore, has 
Tecorded some of his observations in the tropics on the dispersal 0 : 
He uses three categories: (1) winged fruits and seeds; (2) plumed fruits and seeds 
and (3) « powder-seed,” by which he means such fine and dust-like bodies as the 
Seeds of orchids and the spores of ferns. The nature of the observations a 
be illustrated from the account of Shorea leprosula (Dipterocarpaceae)- sak 
sreatest distance the winged fruit of this species was observed to travel supe ane 
tier yards,” which is much more than the usual distance. The giewe s «300 
Set the most favorable circumstances the species can SPre# 
* STEINER, R. S., Ber. Deutsch. Bot. Gesells. 23:15. 1995- ucaria 
“Oe pgnage G., Ueber die Vielkérnigkeit der Pe ga 
thr #i Hook. Vorliufige Mitteilung. Ber. Deutsch Bot. Geselis. 
J+ Igos. 
Rwiey, Henry N., On the dispersal of seeds by wind: 
30 Annals of Botany 
19: 351-363. 1905 
