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SUMMARY OF CURRENT RESEARCHES RELATING TO 
eight species of Agaricacem, and has illustrated them by photographs 
from the fresh specimens. Several are European, others known only 
from the United States, A. L. S. 
Philippine Basidiomycetes : IV. — Paul W. Graff ( Torreg Bot. 
Club, 1921, 48, 286-95). The author states “that the fungous flora 
of the tropics is proving to be much more extensive than had previously 
been imagined.” In this paper he deals entirely with Polyporeae, and 
the list contains some rare and interesting records, though none of 
those described are new to science. A. L. S. 
Mycorrhizas of Pinus silvestris and Picea alba. — Elias Melin 
( Journ . Ecology , 1922, 9, 254-7). The author has published as a pre- 
liminary note an account of work done by cultures with ectotrophic 
Mycorrhizas. He has isolated and tested three forms of mycelium from 
Pinus sylvestris and one from Picea. In addition a dark coloured 
mycelium which attacks the seedlings parasitically was also grown. 
The mycorrhizal fungi are aerobic organisms which grow more vigorously 
in an acid substratum. Organic nitrogen compounds form a more 
valuable source of nitrogen for these fungi than inoganic ones. Pre- 
liminary experiments indicate that at least the Mycorrhizas of Pinus 
sylvestris fix the nitrogen of the air. The author dissents from 
MacDougal’s view that the tree is not benefited by association with the 
fungus. A. L. S. 
European Canker on the Pacific Slope.— S. M. Zeller and C. E. 
Owens ( Phytopathology , 1922, 11, 464-8, 4 figs.). Canker on apple ; 
due to the fungus Nectria galligena has been reported from several 
localities in Oregon and California. Many varieties of apple-trees have 
been attacked. The author describes the fungus, and illustrates the 
damage done to branches and stems by photographs of the diseased | 
areas. The mycelium of the fungus penetrates the tissues and destroys 
the cambium. A. L. S. 
Septogloeum Arachidis, Leaf-spot of the Peanut in South Africa. 
— Van der Bijl ( Union of South Africa Journ. Dept. Agric ., 1920, 1, 
528-30, 2 figs. ; see also Bull. Agric. Intell. Rome , 1921, 12, 364-5). 
In South Africa, especially along the coastal region of .Natal, the 
peanut is often attacked by Septogloeum Arachidis , which forms circular 
or irregular black spots on leaves and stems. The diseased leaves 
wither and fall off . Various methods of treatment for the disease are 
recommended. A. L. S. 
Decay of Brazil Nuts. — Edwin Rollin Spencer (Bot. Gaz ., 1921, 
72, 205-92, 5 pis., 3 figs.). Brazil nuts suffer in- transport and in 
storage from the attack of fungi and bacteria. The writer of the paper 
has succeeded in isolating seven distinct organisms, and describes their 
development and their effect on the nuts. Fully 5 p.c. of all diseased 
nuts are affected with a black crust on the endosperm, which bears 
pycnidia and colourless simple spores. He names this fungus Pelioniella 
macrospora. A white mould, less frequent but very pernicious, was 
determined as Gephalosporium bertholletianum ; the mycelium of the 
