334 Pickett: A sTUDY OF CHEILANTHES GRACILLIMA 
similar cultures shaded by the first, which were immediately 
above them. Exchanging the positions of these dishes made 
sufficient change in light intensity to produce marked changes 
in the growth of the sporelings. Very nearly the same peculiari- 
ties of form appeared when plants were allowed to develop 
under water. Fics. 10 and 25 represent extreme cases of 
irregular development under water. These, being antheridial 
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Fic. 21. Sporeling showing tendency for proliferation through multiple 
growing points. Fic. 22. Marginal proliferation following injury to young 
plant; dotted lines show injured cells. Fic. 23. Unusual production of 
growing tips in three or more planes. Fic. 24. Unusual growth of marginal 
cells in sinus. Fic. 25. Greatly elongated antheridial plant developed 
.under water. ‘ 
plants, would be expected to show irregular growth, but they are 
much more attenuated than plants grown on the surface of 
culture fluid or on soil. Fic. 25 is that of a plant developed 
wholly under water in normal light. 
The soil cultures grew nicely up to April, 1922. At that 
time some cultures were flooded and within a month showed 
abundant sporophyte growth. Other cultures were allowed to 
