74 Wilcox — Winter Condition of the Reserve Food, etc. 



starch and other cell contents throughout the entire year. Two 

 associated questions are being examined in connection with the 

 foregoing, (1) the determination of the behavior of the leuco- 

 plastids in the starch-bearing cells in the stems of our decidu- 

 ous trees during this period of dormancy, and (2) the part 

 which the intercommunicating threads of protoplasm play in 

 the translocation of starch. 



Questions in regard to the partial transfer of protoplasm 

 itself inward from the cortex and back again at certain periods 

 are being incidentally examined. 



The slight changes in the reserve food material during the 

 period of dormancy have an important bearing on the interest- 

 ing speculation as to the relation existing between plants of 

 temperate climates and their possible ancestors which thrived 

 under the conditions of a warmer and more equable climate. 

 The relations of all this to the question of biological protections 

 are sufficiently obvious. 



Botanical Laboratory of Harvard University, May 14, 1898. 



Bibliography. 



[Below are given those papers that are referred to in this article.] 



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 Famintzin, A. u. Borodin, J., '67: Ueber transitorische Starke- 



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