THE ETHERIZATION OF PLANTS, 81 



made November 11 gains of from two to eight days were secured 

 from ether; ethyl bromide and methyl chloride gave a gain of 

 twenty-three days; while ethyl iodide only gave a two days increase. 

 Plants etherized January 13 gave gains of from three to five days, 

 while those treated with ethyl iodide were accelerated two to three 

 days. The control plants of November 11 began leaf development 

 January 9 while those of January 13 began to grow January 27; 

 the plants of the first date requiring fifty-nine days to begin growth 

 as against fourteen days for the latter period. 



From the above data it will be readily seen how important it is, 

 at least from a purely scientific point of view, that we should have 

 a more intimate knowledge of the rest period of plants. If we 

 could have a growth curve worked out for the various classes of 

 forcing plants, more particularly the woody ones, this growth 

 curve to find expression in both leaf and flower development, and 

 to extend over the whole period from the development of leaf and 

 flower buds to the close of the after rest period, what an illuminating 

 and instructive study it would make. This inquiry is not a dream, 

 nor is it impossible of solution. Much work has already been done 

 but inasmuch as it does not cover the whole rest period it is of a 

 more or less fragmentary nature, and chiefly valuable as a guide 

 to further inquiry. 



The diagram which I have constructed (see page 80) to represent 

 this growth curve is of course very largely diagrammatic. So little 

 is knowTi, at least based upon accurate experimental observations, 

 about the early and central rest period that it is not possible to 

 secure any more than an approximate concept of what the curve for 

 that period should really be. How near it will approach the zero 

 line or the minimum number of days to bring the plant into bloom 

 in the first period of early rest or how far it will de\aate from the 

 maximum number of days in the deep or central rest period we are 

 unable to judge. The growth curves presented are only intended 

 as a suggestion of what the actual growth conditions may be during 

 the rest period of the plant. 



