ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 589 



alboatrum. In artificial cultures it produces first of all white mycelium 

 and conidiophores, but in time a black submerged mycelium is formed. 

 The black mycelium is also produced in potato stalks, and causes the 

 blackening of the tissues. The first visible symptoms of disease are the 

 gradual desiccation and death of the plants ; the fungus which inhabits 

 the wood vessels passes down into the tuljers, and if these are planted 

 the disease spreads again to the new growths, though it has also been 

 proved that diseased tubers may produce healthy plants. 



The disease is not as yet common in the British Isles ; but if it 

 became prevalent the consequences might be very serious. The most 

 satisfactory preventive measures are to maintain a proper rotation of 

 crops, and to take steps to ensure that the potatoes used for seed 

 purposes are healthy. 



Smut Disease of Bamboos. *^ — Flora W. Patterson and Vera K. 

 Charles give an account of this disease, Ustilago Shiraiana Hennings. 

 It was found on timber bamboos that were being transported from 

 California to other suitable districts in the United States for economic 

 planting. The disease is of extreme virulence, and may quickly destroy 

 a whole forest of bamboos. It is prevalent and destructive in Japan, 

 from which country the species of bamboo in question, Phyllostachys 

 kenonis, had been imported into California. The fungus always occurs 

 on the young and growing points of branches, causing them to swell 

 somewhat under the leaf-sheaths, though there is no external dis- 

 coloration. The growth of the branches is arrested, and as the external 

 coverings fall away the sooty fungus is laid bare. Burning of all 

 diseased plants is the only sure means of eradicating the fungus. 



Schizophyta. 

 Sdaizomycetes. 



Studies on Shiga's Bacillus.! — M. Xicholle, E. Debains, and 

 G. Loiseau have studied Bacillus dysentcrise Shiga in relation to its 

 morphology, toxicity, agglutination reactions, and preparation of specific 

 anti-toxin. The organism is non-motile. Gram-negative, and the 

 cultures exude an odour of chestnuts. Colonies upon agar and on 

 broth resemble those of typhoid, but are more luxuriant. When the 

 medium used is moderately alkaline, a ring is formed at the surface of 

 the medium, which if alkaline to phenol-phthaline induces the develop- 

 ment of a scum that re-forms on being detached. A slight yellowish 

 growth is formed on potato, and gelatin is not liquefied. The reactions 

 of the bacillus on the following media are the same as with B. typhosus : 

 milk, glucose broth, neutral and glucose agar, and litmus-lactose agar. 

 It strongly reddens litmus-glucose agar, but does not ferment mannite, 



* Phytopathology, vi. (1916) pp. 351-6 (1 fig.), 

 t Ann. Inst. Pasteur, xxx. (1916) pp. 363-82. 



