ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
S25 
this reaction becomes stronger when the apex of the root has been geo- 
tropically irritated. This is accompanied by a redaction in the quantity 
of a substance which easily gives off oxygen, and which is also normally 
present in the apex of roots. These results were obtained from the 
radicle of Vicia Foba , Lupinus albus , Pisurn sativum , Zea Mays, and 
Cucurbita Pepo , and the coleoptile of Avena saliva. 
Aerotropism in a Saprolegniaceous Fungus.* — In a culture of 
Dicfyuchus monosporus, Dr. L. Oelakovsky observed a constant tendency 
of the germinating filaments to grow towards the margin of the cover- 
glass. Since the conditions prevented the possibility of this growth 
being due to either light or temperature, the author regards it as an un- 
doubted instance of positive aerotropism. The oxygen appears also to 
produce a local branching on the side exposed to its action. 
(4) Chemical Changes (including Respiration and Fermentation). 
Formation of Albumen in Plants.f — Herr W. Zaleski discusses the 
question, with respect to which contrary assertions have been made, 
whether albuminoid substances can be formed in the plant in the dark. 
From a series of experiments on leaves (sunflower), he has come to the 
conclusion that the nitrates taken up into the leaves are there decom- 
posed, and transformed into other nitrogenous compounds. This trans- 
formation is connected with the access of sugar, which renders possible 
the passage of nitrates into other compounds, probably of the nature of 
amides. These processes can take place in the dark. 
Cellulose-Enzyme4 — In addition to the examples already known, 
Dr. F. C. Newcombe records the extraction of an enzyme which digests 
cellulose from seedlings of the date-palm and of Lupinus albus , and from 
the mycele of Aspergillus Oryzse. The author does not agree with the 
suggestion of Griiss that the cellulose-enzyme is identical with diastase. 
In all the above cases the enzyme also dissolves starch ; but the specific 
intensity of action is not the same for starch as for cellulose. The 
Aspergillus ferment is the one which acts most rapidly on the cell-wall, 
the date ferment least rapidly. 
Ammoniacal Fermentation due to MucedineseJ — According to 
M. 0 . Semal, certain simple Mucedineae, such as Penicillium , Aspergillus, 
and Fusarium, cultivated in media containing organic compounds with 
the amidogenous radicle NH 2 , are capable of producing ammoniacal fer- 
mentation. The doubling of the nitrogenous compounds takes place 
with the assistance of a soluble ferment secreted by different fungi. 
This soluble ferment possesses, in the cases examined, an individuality 
belonging to each compound. 
y. General. 
Metamorphosis in Plants. || — Prof. S. H. Vines gives a historical 
account of the theory of the metamorphosis of the foliar organs of plants, 
as taught by Goethe, Wolff, and Linnaeus. The statement that “all 
* SB. K. Bohm. Gesell. Wiss., 1897, No. xxxviii. (11 pp. and 1 pi.) (Bohemian 
with German abstract). 
t Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 536-42. 
% Bot. Centralbl., lxxiii. (1898) pp. 105-8. Cf. this Journal, ante, p. 225. 
§ La Cellule, xiii. (1897) pp. 285-312. 
|| Science Progress, ii. (1898) pp. 79-104, 
