GAGER: CRYPTOMERIC INHERITANCE IN ONAGRA 471 
16. Vries, H. de. The mutation theory. Eng. trans. by Farmer and 
Darbishire. Vol. I. Chicago, 1909. 
17. Vries, H. de. Intracellular pangenesis. Eng. trans. by C. S. 
Gager. Chicago, 1910. 
18. White, J. The ferments and latent life of resting seeds. Proc. 
Roy. Soc. London. Ser. B. 81: 417. 19009. 
Explanation of plates 20 and 21 
PLATE 20 
Onagra biennis. Radium culture, no. 15a, broad leaf. The stigma was pollinated 
with pollen unexposed to radium rays after the ovary had been exposed for 24 hours 
to rays from radium bromid of 10,000 activity in a sealed glass tube 
Fic. a, flower bud, with bract, taken from a lateral branch; b, petal; c, nearly 
mature capsule, with bract (main stem); d, flower (minus corolla); e, leaf from main 
stem. Cf. PLATE 21, and FIG. I and 2 
PLATE Qf 
Onagra biennis. Radiumculture, no. 15a, narrow leaf. For exposure to radium 
rays see legend of PLATE 20 
