No. 578] 



SELF-STERILITY 



cells between which the pollen tube passes, is logical. If 

 the same theory is to be extended to animals, however, it 

 follows that the external portions of the membranes of 

 the animal egg that have been shown by the wonderful in- 

 vestigations of Loeb and of Lillie to have such important 

 functions, must be functionally zygotic in character. I 

 am aware that this suggestion may be considered pretty 

 radical, but it certainly should be given consideration. 

 I do not like to draw an analogy between the animal egg 

 and a pollen grain, but it may be mentioned that in these 

 structures— surely comparable to the animal egg in the 

 fineness of their membranes and walls— both color and 

 shape are inherited as if they were zygotic in nature. 



December 5, 1914. 



LITEEATUEE CITED 



Castle, W. E. The Early Embryology of Ciona intestinalis Flemming (L.). 

 Compton, E. H. Phenomena and Problems of Self -sterility. New Phytolo- 



East, E. M. Inheritance of Flower Size in Crosses between Species of 



The Action of Egg-secretions on the Fertilizing Power of Sperm. 



Archiv. f. Entwicll. d. Org., 40, 205-252. 1914. 

 Hildebrand, F. Ueber die Nothwendigkeit der Insektenhilfe bei der Be- 



fruehtung von Corydalis cava. Jahrb. wis*. Bot., 5, 359-363. 1866. 

 Jost, L. Zur Physiologie des Pollens. Ber. d. deut. bot. Gesell.. 23, 504- 



515. 1905. 



Ueber die Selbststerilitiit einiger BKiten. Bot. Ztg., Heft V and YL 



Morgan, T. H. Some Further Experiments on Self-fertilization in Ciona. 



Biol. Bull, 8, 313-330. 1905. 

 Heredity and Sex. New York. Columbia Univ. Press, pp. ix + 1- 



282. 1913 (page cited 217). 



