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TgT0] BLODGETT—BULBS OF ERYTHRONIUM 343 
stele, the region of fusion being about o. 5 mm. in length (figs. 
16-20). This theoretically constitutes the “hypocotyl” in these 
seedlings (SARGANT 19). © 
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Fic. 1.—Diagram showing development of seedlings: 1, descending axis during 
first stage; 2, inception of droppers and development of root; 3, dropper actively 
elongating downward, second stage of descent. 
First vegetative period 
The cotyledon functions as the first foliage leaf, and provides 
Material for the further descent of the stem apex. Abundant 
stomata and large intercellular spaces are present in the body of 
the cotyledon; moreover it has the power of recovery from wilting 
toa high degree. This was found by allowing the soil to become 
dry and then watering, when seedlings which had become prostrate 
recovered their erect position, unless the cells had actually been 
killed. The cells nearest the tip were the first to show the effects 
of too great drying. 54s : 
Soon after the cotyledon becomes active photosynthetically, 
