

352 4 BOTANICAL GAZETTE [october 



Beach vegetation.— A detailed ecological study of the beach vegeta- 

 tion of that portion of the shores of Lake Michigan which extends from Wauke- 

 gan, Illinois, to Kenosha, Wisconsin, has recently been made by Gates.*: 

 Unfortunately it contains little in the way of quantitative data upon the 

 various factors involved, but as a record of the vegetation of this region it 

 is an admirable and valuable contribution. 



The lack of any definitely fixed conception of what constitutes the unit 

 of vegetation known as a "plant association " is shown not only by the author's 

 review of the literature upon the subject, but also by his subdivision of the 

 vegetation of the very limited area under investigation into more than fifty 

 different associations. Such a multiplication of associations indicates a 

 danger of making the segregation upon a floristic rather than an ecological basis, 

 and also points to the need of some well recognized subdivision of the association, 

 and yet, even with the most conservative treatment, it is to be expected that 

 a region such as this, representing as it does the meeting place of the northern 

 conifer, the eastern deciduous, and the prairie plant provinces, would present 

 an unusual number of vegetational types. The genetic relationship of these 

 various associations is clearly indicated and exhaustive lists of species are 

 given.— Geo. D. Fuller. 



The black oaks.— At the meeting of the American Philosophical 

 Society (Philadelphia) on April 19, 191 2, Dr. Trelease discussed the classi- 

 fication of the black oaks. The abstract of his paper is as follows: Attention 

 to bud and fruit characters has led to a classification of the black oaks quite 

 different from their usual arrangement according to leaf-form, and five groups of 

 species are recognized, three of the Eastern states, one of the Southwest, and 

 one of the Pacific states. The eastern groups are the black oaks (black jack, 

 turkey oak, Spanish oak. and nuerritmn , l «mrW ™L-c (e.r*r\et naV p-rav oak, 



oak 



willow oaks (shingle oak, willow 



Mountain oak) and 



and myrtle oak). The Southwestern olive oaks (Emory's oak and the white- 

 leaf oak) and the Californian holly oaks (evergreen oak, Highland oak, and 

 Kellogg's oak) are less related to one another and to the eastern black oaks 



than these are to one another, and appear to have originated independently 

 of them. 



Nuclear phenomena in the Uredineae.— Weir* 6 has published a 

 brief summary of the outstanding features of the Uredineae, which will be of 

 service to those who wish a condensed outline of the nuclear conditions in the 

 various stages of the life history of rusts.-J. M. C. 



« Gates, Frank C, The 

 southeastern Wisconsin. Illi, 



James 



9-255 



r.w i ■ C tt ' review of the general characteristics and cytologic* 



^Z e T 1 , » C U ' edineae - wit h notes on a variation in the promycelium of Coleo 

 sportum Pulsatilla (Str.). New Phytol. 11:129-139. 1912. 



