76 BOTANICAL GAZETTE [JANUARY 
some new researches on the formation of auxospores in diatoms. Goebel — 
shows that in all observed Muscinez the wall of the antheridium is active in 
dehiscence, and is not merely ruptured by the swelling contents. Went 
points out a periodicity in the blooming of Dendrobium ; Ewart has a general 
paper on physiological research in the tropics; Wiesner describes a new form 
of false dichotomy in the shoots of woody plants; Massart writes on epiphyl- 
lous plants, represented by alge, lichens, hepatics, and mosses. Warburg 
emphasizes the antithesis between the tropical strand flora of America (incl, 
West Africa) and that of Asia (incl. East Africa). Boerlage describes the 
manner of floating and the germination of the fruits of Heritiera littoralis,a 
coast tree of all the Malayan islands. Kamienski describes a new terrestrial 
Utricularia which he dedicates to Treub under the name U. Treubi. Besides 
these there are several other botanical papers of less general interest.— 
. os. : 
IN A PAPER just published’ by Dr. R. H. True and C. G. Hunkel, on the 
poisonous effect exerted on living plants by phenols, the authors summarize 
their results as follows: 
“We find, as far as our knowledge of the dissociation of the phenylic 
compounds permits us to draw conclusions, that, except in isolated instances 
electrolytic dissociation plays but a very subordinate réle in determining the 
toxic properties of these substances. Picric and salicylic acids strongly dis- _ 
sociate and become powerfully poisonous by virtue of the H ions, in great 
measure. Pyrogallol and probably methyl salicylate first undergo other 
molecular changes, after which their products dissociate electrolytically. 
Here the H ions may account for much of the toxic action. In the cresols 
and mono-nitrophenols, electrolytic dissociation seems to exert a pronounced 
influence. Some phenols are comparatively weak in their integrity, but 
quickly change to substances containing constituents even more fatal than 
lons. Pyrocatechol, and especially hydroquinone, are of this class. 
group (CH (CH;)2) into the cresols increases the toxic value of these SU 
stances, as carvacrol and thymol. The presence of one or more nitro groups 
(NO,) increases the toxic action to a great degree; ¢. g., mono- and ‘ 
nitrophenols. An increase in the number of the NO, groups present does ™ 
Seem to increase the toxic action. When the H of an OH group is repi@ 
5 Botanisches Centralblatt 76 : — seqq. 1808. 
