140 
The treatment of the Zygomycetes is substantially the same as for 
the preceding series: first, fourteen pages outlining the main features 
of the order Mucoringe, then a key to the genera, followed by a descrip¬ 
tion of the species of the genus Mucor as far as the end of the first sec¬ 
tion, Mono-Mucor. 
This volume, while devoted to the forms occurring in Germany, Aus¬ 
tria, and Switzerland, can not fail to be of great service to American 
students, since many of the described species occur in this country. 
Eeference to doubtful forms and extra-European ones also help to make 
the book indispensible. —Erwin F. Smith. 
Fruit culture in foreign countries .—Reports from the consuls of the 
United States on fruit culture in their several districts in answer 
to a circular from the Department of State. Washington, Govern¬ 
ment Printing Office, 1890, pp. 391-937; Index, i-xiii. 
This report is devoted principally to the citrous fruits, the olive, fig, 
and vine. Incidentally there are many references to the diseases of 
these plants, parasitic and nonparasitic. Some of the statements need 
to be taken cum grano sails because emanating from men not specially 
trained to observations of this kind, but on the whole the reports aj)- 
pear to be well written and will prove useful. A similar volume on the 
stone fruits of the world would be equally valuable. —Erwin E. Smith. 
Mangtn, Louis.—(1) Sur la callose , nouvelle substance fondamentale 
existant dans la membrane. Comptes Rendus, Paris, tome cx, 24 
Mars, 1890, p. 644. 
(2) Sur les reactifs colorants dcs substances fondamentales de la 
membrane. Comptes Rendus, Paris, tome cxi, 15 Juillet, 1890, p. 
120 . 
(3) Sur la structure des Peronosporees. Comptes Rendus, Paris, 
15 Ddcembre, 1890, p. 923. 
(4) Sur la desarticulation des conidies chez les Peronosporees. Bull, 
de la Soc. Bot. de France. Comptes Rendus des Seances, Paris, 
1891, tome 38, pp. 176-184, 232-236, pi. 4. 
(1) The author distinguishes three fundamental substances in the 
cell walls of plants—pectin compounds, cellulose, and callose. The 
latter has been studied quite carefully, and is described as a new fun¬ 
damental substance, known hitherto only from sieve tubes. Not hav¬ 
ing been able to isolate it in sufficient purity for a chemical analysis, 
the author confines himself to an account of its distribution in plants. 
Callose is colorless and amorphous, insoluble in water, alcohol, and 
SchweizePs reagent,* even after the action of acids; very soluble in 
soda or cold caustic potash 1 to 100, soluble cold in sulphuric acid, 
chloride of calcium, and concentrated bichloride of tin; insoluble cold 
in the alkaline carbonates, and in ammonia, which swells it and gives 
it a gelatinous consistency. Besides aniline blue and rosolic acidt 
*Cuprammouia. 
t Known also as corallin, aurin, peonin. 
