330 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Germination and Growth of Fungi at various Temperatures, etc. 
— W. Brown (Ann. Bot ., 1922, 36, 257-83). The author gives results 
of many laboratory experiments with Botrytis , Fusarium and Alternaria , 
the fungi on stored fruits. He records that oxygen pressure has little 
effect on their germination and growth ; that their growth is retarded 
by carbon dioxide, and more especially at low temperatures, in a weak 
nutrient or in a dense sowing of the spores. The economic importance 
of the paper refers to gas storage, which, as indicated by the writer, 
may be most effectively used in combination with cold storage, and will 
also give the best results when the fruits to be stored are free from 
growing fungi. A. L. S. 
Sexuality of Basidiomycetes. — Plantefol (Ann. Sci. Nat. Bot., 
1921, ser. 10, 3, xxxiii-xli). The writer has taken up and completed a 
paper projected by the late Professor L. Matruchot on the work of Mdlle. 
Bensaude. He gives a full account of the work on the fusion of nuclei in 
the mycelium of Goprinus fimetarius by means of bridging clamps between 
neighbouring cells of the mycelium near the growing points of the 
filaments. This is regarded as fecundation by the union of two cells, 
similar to what occurs in the Uredinese. The two nuclei of the united 
cells form a dicaryon. A. L. S. 
Studies in the Physiology of Parasitism. VIII. On the Exos- 
mosis of Nutrient Substances from the Host Tissue into the 
Infection Drop.— William Brown (Ann. Bot., 1922, 36, 389-99). 
The writer has studied the question of the effect of the host on the 
fungus before penetration by the latter. He gives an account of his 
methods and of the various experiments. He summarizes his results : — 
1. Drops of distilled water which have lain on the surface of leaves 
show increased conductivity. 2. Though there is increase in con- 
ductivity, that is not always accompanied by increased capacity of spore 
germination. 3. Increased germination, however, runs parallel with 
conductivity. 4. The ease or difficulty of wetting the leaf surface is an 
important factor. 5. Indirect proof of the exosmosis of nutrient matter 
can be obtained by a study of the incubation times of infection in 
different cases. 6. The rate of exosmosis into drops containing Botrytis 
spores is identical with that into spore-free drops, up to and for some 
time after penetration by Botrytis has taken place. The rate of 
exosmosis then increases with great rapidity in the case of the infection 
drops. A. L. S. 
Penicillium glaucum and War-bread. — H. K. (Zeitschr. Pflanzenkr ., 
1916, 26, 99-102). The addition of an undue quantity of potato flour 
to rye-bread during the war induced the growth of Penicillium , owing 
to the greater moisture of the bread. The writer discusses the chemical 
contents of the various kinds of flour— wheat, rye and potato — -with their 
water-content, and gives also an account of the action of the fungus on 
the bread. A. L. S. 
Further Research on the Variations of some Species of Micro- 
mycetes. — Elisa Mutto and Gino Pollaci (Atti 1st. Bot. Pavia , 
1920, 17 , 53-7, 1 pi.). The authors have made a series of cultures on 
