ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
375 
than broad, and exhibits only vibratory motion ; it can be cultivated in 
suitable ammoniacal solutions to which no organic matter whatsoever 
has been added. In these solutions the growth of the micro-organism 
is accompanied by the gradual transformation of the ammoniacal into 
nitrons nitrogen ; in solutions inoculated with the pure growth no 
formation of any nitric nitrogen has yet been observed. Solutions 
thus nitrified remain perfectly transparent and pellucid. Though pure 
nitrifying solutions have as yet yielded no growth in gelatin-peptone, 
the authors have not abandoned the hope of cultivating the nitrifying 
organism on this and possibly other solid media. 
y. General. 
Digestive Properties of Nepenthes.* * * § — M. E. Dubois has come to the 
conclusion, from an examination of the fluid contained in the pitchers of 
a large number of species of Nepenthes, that the carnivorous habits 
ascribed to the plant are the result of erroneous observation ; that the 
liquid contains no digestive substance analogous to pepsin ; and that the 
phenomena of digestion attributed to it are due to the presence of 
microbes, and not to any secretion of the plant. 
Absorption of Rain by Plants.j — Pursuing his investigations on the 
adaptations of plants to rain and dew, Herr A. N. Lundstrom replies to 
the objections to his views brought forward by Kny and Wille,| and 
describes further observations on Stellaria media and on several species 
of Tradescantia, in which the internodes are furnished with lines of hairs 
which serve to convey the moisture of the air either to aerial or to 
underground roots, the former being often very difficult to detect. 
Although the quantity of water thus absorbed by the aerial parts is 
very inconsiderable compared to that taken up by the roots, it may be of 
considerable importance to the life of the plant. 
When water falls on a leaf it may be seen to pass along the course 
of the veins, leaving the rest of the surface comparatively dry. 
Kirchner’s Diseases and Injuries of Plants.§— Herr 0. Kirchner 
deals in his excellent manual with the diseases and injuries of plants 
cultivated by farmers, market gardeners, &c. To them, therefore, this 
work chiefly appeals, although the botanist and zoologist may be 
indebted to it. The work is divided into two sections ; the first of these 
deals with the various plants met with in North and Mid-Europe and 
the diseases to which they are liable, and the diagnosis, treatment, and 
prevention of these maladies. The second portion of the work describes 
the various animal and vegetable organisms alluded to in the first part 
as causing or being connected with the various diseases. 
* Comptes Rendus, cxi. (1890) pp. 315-7. 
f Bot. Sekt. Naturw. Studentsallsk. Upsala, Dec. 11, 1888. See Bot. Centralbl., 
xliv. (1890) pp. 391 and 424; xlv. (1891) pp. 7, 41, and 76. Cf. this Journal, 1887, 
p. 119. 
I Of. this Journal, 1887, p. 995. 
§ Stuttgart, 1890, 637 pp. See Centralbl. f. Bakteriol. u. Parasitenk., ix. (1891) 
pp. 22-3. 
