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proper conditions the seed .absorbs water and the embryo lengthens by 

 growth both above and below the plumule. The growth of the cotyledon- 

 ary petiole is more rapid than that of the radicle, so that the radicle, 

 with the i)huuule, is soon pushed outside the seed coat. The cotyle- 

 donary petiole reacts to the stimulus of gravity so that the radicle is soon 

 directed downward, Fig. 2. The one cotyledon remains inside the seed as 

 an absorbing agent. Fig. 4. The radicle grows down rapidly to form a 

 primary root. Later one or two other roots may be formed. Immediately 

 after the establishment of a root system or water absorbing system, the 

 portion just below tlie plumule becomes enlarged by the storage of food 

 stuff transferred from the endosperm of the old seed, Figs. 3 and 4. 



In case the germination is complete, the formation of a root system is 

 followed by the growtli of the single simple leaf up from the plumule, 

 through the cotyledonary petiole to the light. Fig. 6. Usually, however, 

 only scales are formed around the bud. In either case, when the food 

 material has been absorbed, the tissues connecting seed and seedling 

 shrivel up, leaving the young plant independent. After a period of about 

 eight weeks from the beginning of germination the corms will be found 

 free from the seed and with the roots detached and broken down, all 

 ready for a period of rest, Fig. 5. 



It may be of interest to note that 1. Unicontiiiiii gives other evidence 

 of incomplete response to seasonal changes. iHiring the sunuuer of VdVA 

 the corms of a considerable colony were dug up Idr experimental pur- 

 poses. Although these corms were scattered in the soil but a few inches 

 apart, and some had shown very vigorous growth of stem and leaves, 

 about lialf of them had made no start toward growth. The conditions 

 were certainly the same for all individuals of the colony, and were good, 

 as shown by the growth just mentioned. Whether this ])lant is subject 

 to definite periodicity recpiiring more than the usual rest season, or is 

 controlled by some as yet unconsidered influence, can only be left a 

 question. 



