DISEASES OF PLANTS. 1141 



treatiuf?. while in the other tlie seed wiis not dried l>ut wiis hunj,' in liiigs in iin 

 open shed so that the suporfinous moisture would drain away. The results 

 obtained are not altogether conclusive, as beyond the fact that the seed treated 

 with hot water became moldy and half rotten but little effect was noted which 

 could l)e attributed to the treatment. 



In testing the relative merits of the different treatments for the prevention 

 of snuit. formalin and cojiper sulphate treatments were used, and the etticiency 

 of the copper sulphate was found to be in proportion to the strength of solution. 

 Where copper sulphate in the proi)()rtion of 1 part to 100 was used its efficiency 

 was about the same as where formalin was employed. 



A series of experiments to determine whether formalin or co])per sulphate 

 treatment would jirevent reinfection with snuit was carried on with a number 

 of varieties of wheat, in which the seed was treated and afterwards infected 

 by the introduction of a large number of spores of the fungus. This series of 

 experiments indicated that the protective layer or film of copi)er about the seed 

 is quite beneficial, while formalin, as a protection against reinfection, has but 

 slight effect. 



In experiments to determine the effect of the different fungicides on seed 

 grain when planted in ground too dry for the seed to germinate, the results 

 varied with the different varieties. It appears that for seed lying dormant in 

 dry soil for a jieriod of 4 months there is no need of a protective film such as 

 would be de]H)sited I)y the fungicide. 



Ustilago maydis on the adventitious roots of corn, .T. Chifflot (Compt. 

 h'end. Acad. Sci. \l'(iris\. I.',', (1901), .\o. l-'i, pp. 16.'t-766). — Tlie author reports 

 having observed on the adventitious roots of maize undoubted evidences of corn 

 smut, and by inoculations he was able to produce the hypertrophied tissues- 

 characteristic of the presence of the fungus. 



The raising of strains of plants resistant to fungus diseases, E. E. Salmon 

 {Report of the Third Inter nut ionnl Conference, 1906. on Genetics. London: Roy. 

 llort. Soc.. 1901, pp. SIS-SHJ,). — The author calls attention to the desirability of 

 investigators devoting their work more largely to the i-aising of cultivated plants 

 which are resistant to fungus diseases, and points out the varying susceptibility 

 of different individuals to i)arasitism. He also states that different varieties 

 of cultivated plants show very different constitutions with respect to fungus 

 diseases, and tliat where such constitutional characters have been tested they 

 have been found to be fixed for the species, variety, or race, and to transmit 

 their inununity or susceptibility to tlieir progeny, the characters appearing 

 unclianged in the hybrids. 



Ascogenous forms of Glceosporium and Colletotrichum, C. L. Shear and 

 Anna K. Wood (Bot. (Jaz.. .',3 (1907), \o. }, pp. 2.i9-266).— On account of tlie 

 importance of better information regarding the life histories of fungi, the 

 authors studied a number of forms and have succeeded in growing both the 

 conidial and ascogenous stages from 8 different hosts, as follows: Glocosporiiun, 

 nifoinacnUins from grapes, G. friieti(/enuni from the apple, an api)arently unde- 

 scribed (Jkeosporium from the cranberry, G. ela.'iticw from the leaves of the 

 rubber plant, a form from the honey locust, one from Ginkgo biloba, Colleto- 

 tricJiinn (josxypil from cotton, and C. lindcmuthiannm from cultivated beans. 

 Of these the ascogenous form of only one had been hitherto reported. 



The authors found that in attemi)ting to make pure cultures they would fre- 

 (jueiitly fail to secure the ascogenous form, but that once obtained it could be 

 successfully grown on various media and under various conditions for several 

 generations. 



Heretofore forms of these fungi occurring on different host plants have been 

 regarded as distinct species, but the authors' studies have led to the conclusion 



