186 SUJIMAEY OF CURllENT KESEARCHES. 



resulted in tlie discovery that .the disease is due to the eel-worm^ 

 Tyhnchis devasiatrix. Fusariimi is constantly present, and two species 

 were isolated and grown in pure cultures during the course of the 

 investigation. A. L. S. 



Rhizoctonia on Lawns and Pastures.— C. V, Piper and H. S, 



Cox {Phytopathology, 1919, 9, 89-92, 2 pis.) have been for some time 

 investigating the damage done to golf courses, etc., by the fungus 

 Rhizoctonia Solani. The disease attacks the growing plants, which 

 quickly become brown and die off. It is mostly grasses that are 

 destroyed in these areas, but other plants present, such as Cerastium 

 vulgatum, Achillea millefolium, etc., are likewise affected. Advice is 

 given as to dealing with the trouble. A. L. S. 



Silver-leaf in Fruit-trees. — A paper on this subject has been 

 published {Journ. Board, of Agric, 1919, 26, 102-8, 2 pis.) both in the 

 Journal and as a leaflet of the Agricultural Board. The disease is 

 definitely traced to the action of Stereum purpureum, and the work 

 done by F. T. Brooks on the subject is cited. Other causes may 

 originate " silver-leaf," but so rarely that they are practically negligible 

 in a study of the disease from the grower's point of view. Various 

 recommendations are made as to the treatment of the affected trees 

 and of the soil. Certain varieties of plum-trees have been proved to 

 be resistant, and these should preferably be planted. A. L. S. 



Undescribed Species of Ophiodothella on Ficus. — This Dothi- 

 deaceous fungus has been described by Ernst A. Bessey {Mycologia, 

 1919, 11, 55-7, 1 pi.). It grew on Ficus aurea, in the vicinity of 

 Miami, Florida. The stromata of the fungus occupy yeUowish-green 

 spots on the leaves. When strongly infected the leaves fall in great 

 numbers. The species is fully described and figured. A. L. S. 



Two Illinois Rhubarb Diseases. — Two diseases of market rhubarb 

 have been investigated by Frank Lincoln Stevens {Univ. 111. Aqric. 

 Exp. Stat. Bull., No. 213, 1919, 299-312, 18 figs.). The first, called 

 " rhubarb anthracnose," due to CoUetotrichum erumpens Sacc, causes soft 

 rot of the petioles and renders them unsaleable. Stevens discusses the 

 systematic position of the fungus ; he finds ten nearly related forms on 

 different hosts. 



The second disease dealt with is a Phyllosticta, which occurs on 

 spots on the leaves as well as on the petioles. Successful cultures 

 were made, and, when thickly sown, growth from spore to spore took 

 place in thirty-six hours. Stevens has decided that the species agrees 

 in the main with P. straminella, recorded on Rumex acetosa. A. L. S. 



Notes on Parasitic Fungi in Wisconsin. IV.-VI. — These notes, 

 published by J. J. Davis {Trans. Wise. Acad. Sci. Arts and Letters, 1919, 

 19, 671-727, Part II.), cover a large field of microfungi, many of them 

 already described, but their descriptions are now enriched by biological 

 notes. A number of new species are also published. An index of the 

 hosts as well as of the parasites is appended. A. L. S. 



