Vernalization 



AND PhOTOPERIODISM 



Plate 2 

 to face p. fi'i 



GuSTAV Gassner (b. 18S1), German plant physiolo- 

 gist who was forced to go abroad and became Director, 

 Central Institute of Plant Pathology in Ankara: now 

 Rector, College of Technology, Braunschweig. — After 

 a painting by Fred Harding (based on a photograph), 

 coiirtfsy Univ. of Minnesota. 



Georg Klees (23 Oct. 1857-15 Oct. 1918), the great 

 German plant physiologist and experimental morpholn- 

 gist, longtime Professor of Plant Physiology at the 

 Univ. of Heidelberg. — After a paintin.g by Fred Hard- 

 ing (based on a photograph), courte.iy Univ. of Min- 

 nesota. 



T. D. Lysfxko (6. 1898), the well-known Russian 

 agronomist. — After a painting by Fred Hardint, (based 

 on a photograph), courtesy Univ. of Minnesota. 



NiKOLAj .\lexandrovich Maximov (6. 1880), the 

 distinguished Russian plant physiologist, after a paint- 

 ing by Streblov (based on a photograph), courtesy of 

 Mrs. Harvey. 



