22 



I have also found that there is no segregation of tannin 

 during the ripening process, and this result was extended to 

 the persimmon, (Diospyros), though the contrary view 

 has been held. The work has been published under the 

 title "The development and nutrition of embryo, seed and 

 carpel in the date, Phoenix dactylifera, I.." in the 21 st An- 

 nual Report of the Missouri Botanical Garden, and reprint- 

 ed for liminted circulation. 



My work on the date naturally led me to a consideration 

 of the persimmon, with particular reference to the behavior 

 of the tannin-cells during ripening. As is well known, the 

 great need of the persimmon grower is the ability to process 

 persimmons after the fashion of the Japanese, and it was 

 deemed that a more precise knowledge of the role of the 

 tannin would contribute toward this end. I have found 

 that the disappearance of astringency during ripening is 

 due to the union of the tannin with a second colloid body, 

 also secreted within the tannin-cell, to form an insoluble 

 and imputrescible colloid-compound. It has also been 

 shown that there remains a certain amount of soluble 

 tannin and I have shown that this, under certain conditions, 

 escapes from the tannin-cell and unites with a substance, 

 probalily pectose, which is derived l:)y digestion of the mid- 

 dle lamella. These views harmonize with certain observa- 

 tions of Vinson on the heat relations of ripening in the 

 j:late, and throw light on the data obtained by Bigelow, 

 Gore and Howard, on the persimmon, thus enabling us to 

 imderstand better the nature of the ripening process in 

 these fruits. It may be added that the recently published 

 work of Gore on the relation of carbon dioxid to ripening 

 in the persimmon, following on Prinsen-Geerligs' results on 

 the banana, will lead, I believe, to a solution of the method 

 of processing fruit in a practical way. My own studies 

 have in part appeared under the title. "The behavior of 

 tannin in persimmons, with some notes on ripening," and 

 are in part ready for the press in the form of two additional 

 papers, (i ) "The artificial ripening of persimmons," read at 

 the last annual meeting of the Alabama Horticultural 

 Society, and (2) "The nature of the tannin cell in the per- 

 simmon, Diospyros." 



The Adams Fund prc:iject on transpiriation and allied 

 phenomena in the cotton has progressed. It was found 

 very dift'icult to get material to grow well in the Depart- 

 ment greenhouse on account of the inadequate heating and 



