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BOTANICAL GAZETTE 



The results of this work have been so convincing that the cultivation of disease- 

 resistant strains of our crop plants promises to be the final method of eliminat- 

 ing disease.-J. M. C. 



Ascospore expulsion of Endothia.— Heald and Studhalter 2 ? have pub- 

 lished the results of an investigation of the chestnut blight fungus, which 

 uncovers a very interesting situation. There is a remarkably prolonged 

 perithecial activity, due, partly at least, to three important features in the 

 development of the fungus. The asci mature successively through quite an 

 extended period, the perithecia mature successively in a given stroma, and 

 the stromata mature successively throughout the season. The practical result 

 is that ascospores are available for expulsion at any time when the conditions 

 favor. Expulsion "begins in the spring with the first warm rains, and 

 increases to a maximum of activity as conditions become more favorable, to 

 be followed by a decline in the fall when lower temperatures prevail, and ceases 

 entirely during the cooler portions of the year." — J. M. C. 



Carpophores of pore fungi— Zeller 28 has studied the development of the 

 .carpophores of Ceriomyces Zelleri, one of the pore fungi. He discovers that in 

 this development there is a homogenous mass of tissue which is differentiated 

 simultaneously into pileus and stipe by a cleavage plane which gives rise to an 

 annular furrow, and that the hymenium, which is exogenous in origin, is formed 

 in the roof of a furrow. This form proves to be gymnocarpic, since there is no 

 marginal veil— J. M. C. 



Morphology of Agaricus.— Atkinson 2 * has described in great detail the 

 development of Agaricus Rodmani, a species described by Peck in 1885. The 

 four features which he considers are (1) the duplex character of the annulus, 

 (2) the origin of the hymenophore fundament, (3) the differentiation of parts in 

 the primordial ground tissue, and (4) the origin and development of the 

 lamellae. The paper must be referred to for the numerous details involved.— 

 J. M. C. 



New species of rust —In working over cultures of rusts in connection with 

 their presentation in the North American Flora, Arthur and Fromme^ 0 have 



Uredo.—J. M. C. ? P * ^' 



1 Heald, F. D., and Sttjdhalter, R. A., Seasonal duration of ascospore expulsion 

 of Endothia parasitica. Amer. Jour. Bot. 2:429-448. figs. 6. 19 15. 



38 Zeller, Sanford M., The development of the carpophores of Ceriomyces 

 Zrllrri. Mvcologia 6:235-239. pis. 140, 141. figs. 12. 1914. 



29 Atkinson, Geo. Morphology and development of Agaricus Rodmani. Proc. 

 Amer. Phil. Soc. 54:309-343. pis. 7-13. 1915. 



3" Arthur, J. C, and Fromme, F. D., New species of grass rusts. Torreya 15: 

 260-265. 1915- 



