348 EXPERIMENT STATION RECORD. 



siirayiiig witli Bordeaux mixture. The cutting out of diseased tissues aud the 

 scorching of the wounds, after which they are covered with hot coal tar, has 

 proved successful In a number of instances. 



The biology of Polystictus versicolor, Jessie S. Bayliss {Jour. Econ. BioL, 

 3 (1''08), Xo. 1, PI). l-2.'i. pis. 2). — A study of bilology of P. versicolor Is reported 

 and the fungus is said to be a pure saprophyte, whose natural habitat is moist 

 dead wood.. The author has found it growing on Qiicrcus robiir, Fraxinus excel- 

 sior, Pyrits aucuparia, Salix alha, Bctiila alba, Pyrus mains, Lif/iistrum vulgare, 

 and Cratwgus oxyacantha, and has been able to infect without difiiculty small 

 blocks of Fraxinus excelsior, JJlmus eampcstris, Pruiius avium, Alnus glittinosa. 

 Acer pseudoplatanus, ^scidus hippocastanum, and Betula alba. She has also 

 successfully cultivated the fungus from spore to spore. It seems probable from 

 the investigations reported that it will grow on almost any kind of wood except 

 that of conifers. 



The spores and their germination ar-e described, after which an account is 

 given of the method by which the destruction of wood takes place. The chemical 

 changes seem to indicate that it attacks aud destroys the wood gum, which 

 constitutes a large percentage of the'"wood of most trees except conifers. 



The sporophore of the fungus and the i-elations of the fruiting body to light, 

 gravity, etc., are described, and attention is called to the fact that under 

 natural conditions the pileus lasts but a comparatively short time, being spe- 

 cially subject to the ravages of a small beetle. The spoi'es retain their vitality 

 for a considerable period even when dried or when exposed to high or low 

 temperatures. 



In connection with the investigations the author made the usual tests for 

 enzynis and demonstrated the presence of laccase, rennetase, cytase, invertase, 

 diastase, coagulase, ereptase, and a fibrin-digesting protease. Only negative 

 results were obtained on testing for emulsion, lipase, maltase, and hadromase. 



The chestnut canker, W. A. Murrill {Torreya, 8 (1908), No. 5, pp. Ill, 

 112). — A brief account is given of the author's investigations on the occurrence 

 and spread of the chestnut canker, caused by Diaporthe parasitica (E. S. 11., 19, 

 p. 250), and it is stated that the disease is spreading rapidly. The author 

 claims that not only the native species of chestnut, but also the European and 

 Japanese, which are frequently planted in this country, are subject to attack. 



Experiments in jiruning trees have shown that this is futile as a means for 

 preventing the further spread of the disease. At the present time the author 

 thinks that planting any species of chestnut in an affected area would be at- 

 tended with great risk. The owners of chestnut timber are advised to make use 

 of their timber at once, thus clearing the woodlands of the sources of infection 

 and giving young trees of other varieties opportunity to develop. 



The bleeding and yellowing of poplars, J. W. Blankinsiiip (Ztschr. 

 Pflanzrnlcnink., IS (1908), No. 1, pp. 26-28). — Further notes are given on 2 

 diseases of poplars termed by the author bleeding and yellowing, of which pre- 

 liminary accounts have already been given (E. S. R., 17, p. 451). These dis- 

 eases are said to attack various species of poplar, particularly Populns aiiyusii- 

 folia, P. balsamifera, P. trichocarpa, and P. deltoides. 



The principal characteristic of the bleeding is the exudation of sap from the 

 wounds in the affected tissues. This disease the author believes is due to 

 bacteria, since the sap is full of bacteria, and the inner wood cells of diseased 

 tissues are also found filled with them. Cultures have been made of these 

 bacteria, but further investigations are needed to determine whether the bac- 

 teria are the cause of the disease, and also the role of ants and flies in its 

 distribution. 



