ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
235 
to assume an erect position, and the corolla to be deeply divided. The 
other American species of the genus are enumerated, all, with one excep- 
tion, parasitic on Ericaceae. 
A disease of the apricot-tree which is causing great destruction of 
the crop in parts of Germany, was found by Herr B. Aderhold* * * § to be 
always accompanied by a great development of Cladosporium lierbarum , 
and especially by the form of that fungus known as Dematium pullulans , 
together with a species of Hendersonia ; but whether the former is the 
cause of the disease he was unable to determine. The latter is certainly 
not parasitic. 
Fungus-parasite of Sphagnum.^ — M. S. Nawaschin describes the 
parasitic fungus the spores of which have been described as “ micro- 
spores” of species of Sphagnum. He gives it the provisional name 
Tilletia Sphagni. 
Fungi which produce Citric Acid.J — Herr C. Wehmer has found, 
in carrying on experiments on the production of oxalic acid by fungi, 
a genus, to which he gives the name Citromyces , which has the remark- 
able power of converting carbohydrates into citric acid. Of the genus 
he describes two species, G. Pfefferianus and glaber. Their ordinary 
mode of multiplication is by conids ; but they occasionally produce other 
structures, which may be sclerotes or asci ; and a yeast-like budding 
also occurs. The production of citric acid is in the first place due to 
oxidation of the carbohydrate, and is dependent on the presence of 
oxygen. The most favourable nutrient substratum for its formation is 
a moderately concentrated solution of sugar. To both species the 
parasitic fungus Penicillium luteum is very destructive. 
Spores of Yeast.§ — Herr M. Moeller records fresh experiments which 
disprove the statement of Krasser,|| that no true nucleus is to be found 
in yeast-cells. In the mature spores he always finds, by the use of the 
proper reagent — a preparation of haematoxylin — a membrane and nucleus, 
as also in the vegetative cells. His observations throw no certain light 
on the systematic position of the Saccharomycetes. 
Fermenting Grape- and Apple-must with Pure-bred Yeasts.1T — 
The fermentation experiments made by Herren E. Mach and K. Portele 
with S. cerevisise , S. Pastorianus i. and iii., S. ellipsoideus i. and ii., 
S. apiculatus , and Monilia Candida , on grape- and apple-must, show that 
the quantity of alcohol and glycerin produced depend directly on the 
ferment. Thus, for 100 parts by weight of alcohol, 6*42 parts of 
glycerin were formed by S. apiculatus , 3 • 88 by Monilia Candida , and 
4-68 by S. cerevisise. The last-named yeast produced 11*82 volumes of 
alcohol in the same time that 2 * 9 volumes were produced by S. apicu - 
* Landwirthsch. Jahrb., xxii. (1893) pp. 435-67 (1 pi.). See Bot. Centralbl., lvi. 
(1893) p. 153. 
t Bull. Acad. Imp. Sci. St. Petersbourg, xiii., pp. 349-58. See Bot. Centralbl., 
1893, Beih., p. 526. Cf. this Journal, 1891, p. 73. 
X Comptes Rendus, cxvii. (1893) pp. 332-3 ; and Beitr. z. Kenntn. einheimiseker 
Pilze ; see Bot. Ztg., Iii. (1894), 2te Abtheil., p. 6. 
§ Ber. Deutsch. Bot. Gesell., xi. (1893) pp. 403-9 (1 pi.). 
|| Cf. this Journal, 1893, p. 366. 
If Landwirthsch. Versuchs-stationen, xli. (1892) pp. 233 and 261. See Bot. Cen- 
iralbl., lv. (1893) pp. 57-8. 
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