421 
Proceedings of the Botanical Club, A. A. A. ‘S.--Detroit Meeting, 
August, 1897, 233 
Turspay, AUGUST IOTH. 
In the absence of all officers elected at the last meeting, the 
Club organized by the election of Dr. J. J. Davis, President, and 
Mr. A. F. Woods, Secretary. 
Professor C. E. Bessey described an extensive epidemic of 
Erysiphe communis on Polygonum aviculare about Lincoln, Neb. 
In the ensuing discussion the same occurrence was reported from 
Michigan and Wisconsin. 
Professor Bessey also described a phosphorescent mosquito 
(Chironomus sp.). 
Professor Beal exhibited a number of photographs of the 
Botanical Garden of the Michigan Agricultural College; also 
charts of fungi and mounted sheets of weeds for lecture-room 
purposes. 
WEDNESDAY, AUGUST IITH. 
Mr. Rodney H. True presented “ Notes on the Genus Di- 
cranum,”’ 
Dicranum Spurium in America consists of two forms, the gen- 
uine species and a form differing in many important characteristics 
from any described; the latter has probably a wide distribution 
in eastern America. Dicranum rhabdocarpum in abundant fruit 
has been found on Pikes Peak by Professor J. M. Holzinger. Its 
affinities ally it closely with D. Bonjeani DeNot. and not, as stated 
in the L. & J. Manual, with D. Mihlendeckit. Mr. A. J. Grout 
has collected, probably for the first time in America, Dicranum 
longifolium var. subalpinum on Mt. Mansfield, Vt. : 
Dr. C, E. Bessey spoke on sensitive stamens in Opuntia fragilis ; 
in bright sunlight they were very noticeable, quite as much so as 
in Portulaca, and were subsequently observed in another species. 
Dr. Britton remarked on similar sensitiveness in the stamens of 
the eastern Opuntia Opuntia. 
Professor C. F. Wheeler remarked on two interesting species 
of oaks, discovered by Mr. S. L. Alexander in the vicinity of Bir- 
mingham, Mich., deferring critical dftermination of the species. 
