302 The Plant World. 



economic importance to the crop wastes as sources of all grades 

 of paper. This little circular gives a cheerful tone to the pros- 

 pects for the conservation of the Sunday Edition. 



In a recent bulletin of the New York Botanical Garden Dr. 

 Frank D. Kern has published ' 'A Biologic and Taxonomic Study 

 of the Genus Gymnosporangium. " Dr. Kern has made the 

 usual taxonomic study, in connection with which, as his title 

 in licates, he has carried out several lines of investigation which 

 give his published results far wider interest than is usually pos- 

 sessed by the monograph of a genus. He has made over 200 in- 

 door cultures with a view to confirming and extending our know- 

 'edge of the life cycles He has made a detailed study of the dis- 

 tribution of the species of Gymnosporangium and of the known 

 host plants of its two stages, concluding that the ^^presence of 

 suitable hosts will assure the presence of the fungus, without 

 regard to the environmental factors that are commonly con- 

 cerned in the occurrence or absence of plants. A complete under- 

 standing of the genesis of the present distributional relations of 

 Gymnosporangium cannot be had without further knowledge of 

 the geological history of the movements of the host genera. Evi- 

 dence is brought forward to show that there is a correlation 

 between the suppression of uredospores in Gymnosporangium 

 and the performance of the characteristic functions of uredos- 

 pores by the aecidia and teleutospores. A discussion is also 

 given of the pathological effects, economic importance and con- 

 trol of the genus. 



Dr. F. L. Stevens, of the North Carolina Agricultural Col- 

 lege, who has recently been appointed Dean of the College of 

 Agriculture of the University of Porto Rico, is making plans for 

 the establishment in Porto Rico of a research laboratory for 

 bo tan v and zoology. Of the everal attempts which have been 



