PROCEEDINGS OF THE ACADEMY AND AFFILIATED 



SOCIETIES 



THE BIOLOGICAL SOCIETY OF WASHINGTON 



The 571st regular meeting of the Biological Society of Washington 

 was held at the Cosmos Club, May 5, 1917; called to order by Presi- 

 dent Hay; 25 persons in attendance. 



On recommendation of the Council, Donald R. Dickey, Pasadena, 

 California, and J. Eugene Law, Hollywood, California, were elected 

 to membership. 



Under the heading Brief Notes President Hay exhibited a lantern 

 slide of some very immature flying squirrels. 



The regular program consisted of two communications: 



F. V. Coville : The influence of cold in stimulating the growth of plants. 

 Mr. Coville stated that the spring and summer growing period of plants 

 in regions having cold winters is followed by a period of dormancy 

 which persists if the plants are artificially maintained at a relatively 

 high temperature. A period of exposure to cold is needed to activate 

 the plants for another period of growth. The mechanism of activa- 

 tion appears to be the liberation of enzymes acting on the stored 

 starches, converting them to sugars; it is perhaps a change in the per- 

 meability of the cell membrane. It is normally brought about by 

 cold, but mechanical injury or a period of drying may bring about the 

 necessary changes. The operation is not controlled by the roots but 

 acts independently in any exposed parts of the plants, so that if of two 

 branches of a plant one is kept continually warmed and the other sub- 

 jected to the usual winter chilling the former will not develop on the 

 advent of summer temperatures, while the latter develops normally. 

 Mr. Coville's paper was illustrated by numerous lantern slides. His 

 communication was discussed by Messrs. E. A. Goldman, Wm. Palmer, 

 L. O. Howard, W. P. Hay, and A. A. Doolittle. 



W. P. Hay: The rate of growth in certain lower vertebrates. Professor 

 Hay gave some of his personal observations of the rate df growth of 

 the loggerhead turtle, and observations, based on the published records 

 of others, on the rate of growth of certain snakes and of an alligator. 

 His communication was illustrated by charts and diagrams. 



M. W. Lyon, Jr., Recording Secretary. 



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