852 EXPERIMENT STATION EECORD. 



injured by the presence of tlie fungus. The inoculation material was all taken 

 from diseased red clover plants, and it is possible that the occurrence of the 

 fungus on some of the clovers which has beeo reported by other observers may 

 bo due to the fact that there are different varieties or races of the fungus, aJid 

 that the author's failure to get the fungus to grow on some of the host plants 

 may be attributed to this fact. 



The conclusions of the author state that young clover plants are readily 

 affected by the spores of S. trifolionim, but that older plants are attacked 

 more rarely and only under favorable conditions. The spore infection does not 

 take place through the stomata, but the mycelium always penetrates the epi- 

 dermal cell walls. The fungus attacks the aerial parts of the plant, spreading 

 from them to the roots, never through tlie soil nor from the roots to the aerial 

 stems. The spores retain their vitality for months, even when dried. A strong ap- 

 plication of lime to clover fields did not serve to prevent the growth of the fungus. 



A contribution to the knowledge of the potato plant and its diseases, I, 

 O. Appel (Arh. K. Biol. Anst. Land u. Forstw., 5 {1901), No. 7, pp. 377-435).— 

 A historical and critical review is given of the literature relating to the diseases 

 of the potato. A bibliography of several hundred titles of articles which the 

 author has consulted is api)ended. The summary is arranged according to 

 l^eriods, the first period being from 1571 to 1S3S, the second from 1840 to 1855, 

 and the last from 18.">(i to date. 



Stysanus stemonitis and its role as a potato parasite, O. Appel and W. F. 

 Bruck {Arb. K. Biol. Anfit. Land n. Forstw., 5 {1907), No. 7, pp. JfJfl-U8, figs. 

 5). — An account is given of the disease of potatoes attributed to 8. stcmotiitis, 

 which has been associated in this country with a disease characterized by 

 the browning of the tubers in the region of the fibrovascular tissues (E. S. R., 

 14, p. 203). There appears to be no doubt but that the fungus while usually 

 a saprophyte may also become an active parasite. 



The ring disease or iron spotting of potatoes, A. Mayer {Jour. Laiidu\, 

 5') {1907), No. .'/, pp. 301-304). — This disease has been attributed to various 

 causes, such as bacteria (E. S. R., 10, p. 548), soil conditions, lack of lime, etc., 

 and the author has attempted to determine the question of its being due to a 

 lack of lime. 



Tubers grown in soils containing diminishing proportions of lime were 

 affected in proportion to the deficiency of lime in the soil. An examination 

 of the ash of diseased tubers showed that the lime content was much lower 

 than in normal potatoes. The disease is said to always be worse when potatoes 

 follow spurry or late turaips, although no connection could be found between 

 those crops and the cause of the potato disease. 



Tomato diseases, P. H. Rolfs {Florida 8ta. Bill. 91, pp. 13-3), pis. 3. fif/. 1). — 

 Descriptions are given of the rust of tomatoes due to Marrosporium solani, a 

 r fungus blight caused by Fusariuni sp., a sclerotium blight due to an unrecog- 

 nized fungus, a bacterial blight caused by Bacillus solanaecarum, dropping of 

 the buds, leaf curl, damping off, hollow stem, root knot, and some common 

 insect enemies. 



For tomato rust spraying with Bordeaux mixture is recommended. Rota- 

 tion of crops is suggested as a means for the control of the Fusarium disease, 

 and for the sclerotium blight sjn-aying the soil about the plants with ammoui- 

 tical copper cai-bonate is suggested. 



The dropping of the buds is said to be due to unusually cool weather at the 

 time when the fields are in blooming condition, too great stimulation of the 

 plants by the use of ammonia fertilizers, or the puncture of minute insects. 



The leaf curl is said to be due to a number of causes, the most important 

 one in Florida being the presence of too much moisture in the soil. The rem- 



