ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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mould penetrates and destroys the radicle of the nut. A disease called 
dry-rot is shown by a mottled appearance of the shell, the inside being 
filled with the mycelium of a Fusarium. Many nuts are destroyed by 
Aspergillus flavus : the kernel shrinks, often cracks, and is always 
covered by a mass of dark brown spores. In addition to these fungi, 
Spencer isolated and cultured a Bacterium sp. Actinomyces brasiliensis 
sp. n., which destroys the nuts. He describes finally a decay due to 
Phomopsis bertholettianum sp. n., and notes the presence of a Myxosporium 
which causes bitter rot. A. L. S. 
Onion Smut. — T. Whitehead ( Journ . Board Agric ., 1921, 28, 
451-5). An account of experiments to combat the disease is given in 
detail. The most effective treatment is undoubtedly the application of 
formaldehyde to the open drill, which prevents any spores present in the 
soil from germinating and so infecting the onion seed. An explanation 
of the methods employed is given. A. L. S. 
New Disease of Dates. — Edm. Sergent and M. Beguet ( Oomptes 
Bendus , 1921, 172, 1624-7). The disease is called by the natives 
“bai'oudh ” ; it is spreading in the Moroccan oases, and threatens to do 
much damage. Examinations and experiments have been made, and 
the disease has been found to be caused by a fungus which resembles 
Neocosmospora vasinfecta , a pathogenic organism. The reproduction of 
the disease by infecting healthy date-trees is to be attempted. A. L. S. 
Pathology of Lupinus arboreus. — Arthur S. Rhoads {Phyto- 
pathology, 1921, 11, 389-404, 3 pis.). The shrub Lupinus arboreus , 
the tree Lupine, is of common occurrence in America, on sandy soils near 
the ocean, and is economically of considerable importance as a soil 
retainer in sand dune country. It is subject to rotting caused by two 
wound parasites, Gollybia velutipes and Pleurotus ostreatus, which are 
normally saprophytic fungi. The wounds of the bush plants are made 
by the larvae of a moth. The fungus destroys the cellulose layers 
bordering on the lumina of the wood fibres ; the dissolution starts at 
the lumen and progresses towards the middle lamella, the dissolution of 
the lignified members follow’s. A. L. S. 
Resistance of Barley to Helminthosporium sativum. — H. K. 
Hayes and E. 0. Stakman (. Phytopathology , 1921, 11, 405-11). The 
authors describe the breeding experiments undertaken to secure a race 
resistant to spot-blotch diseases. A certain amount of success has 
been obtained. A. L. S. 
Violet Root Rot (Rhizoctonia crocorum DC.) in the United 
States. — James A. Faris ( Phytopathology , 1921, 11, 412-23). 
Specimens of potatoes covered with a violet felt of mycelium were sent 
to the University of Nebraska. The disease is of minor importance, 
but may become serious and may be propagated by infected tubers. 
Experiments are desirable to find if the fungus is identical with the 
one that attacks alfalfa and sugar beets. The effect of the fungus on 
the tubers is to break the periderm and so induce drying out of the 
potato in storage. The fungus forms small cushions below the 
epidermis which burst through and cause the breaks. A. L. S. 
