miscellaneous: experimental teratosis 607 



over a considerable period, one long enough to produce a dwarf- 

 ing from which the leaf cannot recover. Such leaves look 

 sickly and may fall early. Occasionally, when they are greatly 

 dwarfed, although extremely pimply, they bear very few shoots, 

 as if the latter could not develop for want of food. 



The prolification, I think, can hardly be brought about by 

 starvation which we know may throw dwarfed plants of various 

 kinds into premature or excessive blossoming, since it is common 

 observation that in a great variety of woody plants in full and 

 vigorous foliage there is enough food present in the roots and 

 shoots to make an entire new set of leaves in case the leaves have 

 been destroyed wholesale by caterpillars or by frost, but hardly 

 ever enough for a third set of leaves. Moreover, this begonia 

 may be kept in a small pot for a very long time without starving 

 it into phyllomania. There would appear, therefore, to be an 

 abundance of food in these broad-leaved vigorous plants so that 

 totipotent cells in the embryonic epidermis need not behave as 

 if in the last stages of starvation, even granting that they would 

 proliferate, if starved. 



25. That there is excessive loss of water from the shocked 

 leaves and internodes would seem also to be indicated conclu- 

 sively by the fact that very frequently corky patches are de- 

 veloped on such organs, especially on the internodes (Figs. 

 432, 4343, 437, 4493, and Table III), often entirely surrounding 

 them, while cork is present nowhere else on the plant either above 

 or below. This, I interpret, as a more or less futile effort on 

 the part of the organ to protect itself from loss of water. 



In this connection Series VI is also very interesting. This 

 experiment deals with 59 plants. It was begun on March 5, 

 1919, and the principal dates are as follows: 



March 5. Cuttings made and left to dry on the hothouse 

 bench. 



March 7. Cuttings bedded in sand. 



May 7. Rooted cuttings transplanted to 4 inch pots. 



June 2. Transplanted to 8 inch pots. 



The plants grew splendidly and were mostly unbranched and 

 about 15 to 16 inches high on July 12 to 23 when the tops were 



