PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 



THE PHILOSOPHICAL SOCIETY OF WASHINGTON 



The 41st annual (701 regular) meeting was held on December 9, 1911, 

 President Day in the chair. The meeting was devoted to hearing the 

 annual reports of the secretaries and the treasurer, and to the election of 

 officers for 1912. The following were chosen: 



President: E. B. Rosa. Vice-Presidents: C. G. Abbot, G. K. Burgess, 

 W. S. Eichelberger, L. A. Fischer. Treasurer: L. J. Briggs. 

 Secretaries: W. J. Humphreys, R. L. Faris. General Committee: 

 Wm. Bowie, E. Buckingham. E. G. Fischer, J. A. Fleming, B. R. 

 Green, D. L. Hazard, R. S. Harris, P. G. Nutting, F. A. Wolff. 



R. L. Faris, Secretary. 



THE BOTANICAL SOCIETY OF WASHINGTON 



The 76th regular meeting of the Society was held at the Cosmos Club, 

 Tuesday, December 5, 1911. President W. A. Orton presided. Thirty- 

 three members were present. 



The following papers were read: 



Thrips as pollinators of beets. Harry B. Shaw. 



Thrips tabaci were observed to be numerous on seed beets in Utah. 

 They were always abundant on flowering racemes, as many as 190 being 

 collected from one small branched raceme. They were not observed to 

 interfere with seed production. On the contrary, it appeared more 

 probable that they acted as agents of pollination. An examination 

 showed them to bear numerous pollen grains scattered about their bodies. 

 As many as 140 beet pollen grains being counted on one adult thrips. 

 An experiment, started August 7 and 8, 1911, under carefully arranged 

 isolation conditions on emasculated beet flowers, resulted in 17.2 per cent 

 of the flowers to which thrips had been introduced being fertilized and 

 producing seed. All the controls remained sterile. The conclusions are 

 that thrips are probably important beet pollinators; that they may act 

 similarly with other plants; that their absence or too small number may 

 account for the non-fertilization of flowers in some localities and seasons; 

 that they may fertilize flowers under supposedly isolation conditions 

 and may even cross plants not regarded as capable of being crossed by 

 insects, e.g., barley; and that they may also spread fungus spores and 

 bacteria. 



Forest types. Raphael Zon. 



An ecological survey of the forests of western Idaho, in connection with 

 the preparation of yield tables, revealed three main forest types, or, in 

 the terminology of ecologists, "formations." Two of these are final or 



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