ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
831 
of light, temperature, and oxygen, as well as of the spectroscopic pro- 
perties, of the following fungus-pigments : — the pink pigment of the 
pileus of Russula Integra and vesca , the red of the pileus of Amanita 
muscaria , the orange-red of Paxillus involutus, the yellow of the cortex 
of AEthalium and of the ripe receptacle of Ly cogala epidendron, the dark 
violet of the spores of Fuligo varians, the yellow of Pholiota Jlammans 
and of Cantharellus cibarius, the yellow of the hymene and the yellow- 
brown of the surface of the pileus of Boletus sevens, the yellow-brown or 
red-brown of Polyporus igniarius, the orange-brown of Limacium pratense , 
the red or orange-yellow of Lactarius deliciosus. 
The author classifies the known pigments of fungi under the three 
following heads: — (1) Hydrochromes (pigments of Russula and of 
Amanita muscaria ). These are readily oxidized and reduced, easily 
decomposed by light, soluble in water, insoluble in 95 per cent, alcohol, 
and are fluorescent ; they occur on the surface of the fungus and in the 
membranes of the hyphaB. (2) Lipochromes. None of this group occur 
in the pigments examined by the author. (3) Excreta. The greater 
number of the pigments of fungi are certainly or probably of this 
character ; they are not destroyed by light, and are distinguished from 
those of the first two groups by their greater stability. They often 
occur in the cell-cavity, often outside the membranes of the hyphje, but 
by far the greater number are incrustations of the membranes them- 
selves. 
Pythium Sadebackianum, a Disease of Peas.* * * § — Herr L. Wittmack 
describes a disease of peas caused by a new species of Pythium 
nearly allied to P. Be Baryanum and P. Equiseti. It attacks the 
lower part of the stem, and the root, but especially the root-tubercles. 
It forms sporanges within the tissue, each containing a single spore. 
Cladosporium herbarum.j — Herr G. Lopriore describes the destruc- 
tive effects on corn-crops of attacks of Dematium pullnlans, a conidial 
form of Cladosporium herbarum ; it causes the disease known as “ Taumel- 
getreide,” which shows itself as black streaks on the grains ; and it 
also produces, under certain conditions, chlamydospores with thick brown 
walls. 
Fungus-diseases of the Tomato and of the Date-palm. :{: — MM. E. 
Prillieux and Delacroix describe a very destructive epidemic of the 
tomato produced by Cladosporium fulvum ; it makes its appearance as 
yellow spots on the under side of the leaves. 
The same authors find that the long-known parasite of ripe dates, 
described as Ustilago Phoenicis, is a species of Sterigmatocystis nearly 
allied to S. nigra. A full diagnosis of Sterigmatocystis Phoenicis is 
given. 
Diseases caused by Fungi.§ — Mr. J. E. Humphreys describes a 
number of diseases of cultivated crops caused by fungi: — A disease of 
* Mttl. d. Yer. z. Forderung d. Moorcultur, 1892. See Bot. Centralbl., 1892, 
Beih., p. 316. t Ber. Deutsch. Bot. Gesell., x. (1892) pp. 72-6. 
X Bull. Soc. Mycol. France, vii. (1891) pp. 19-20, 118-20 (1 pi.). See Bot. 
Centralbl., li. (1892) p. 121. 
§ Report on Plant-diseases, No. 23, pp. 218-48 (1 pi.). See Bot. Centralbl., 
1892, Beih., p. 307. 
