418 BOTANICAL GAZETTE [NOVEMBER 
in which both stamens and ovary are early involved in strong 
degenerations. There is also a degeneration of the filament cells, 
severing the maturing anthers. 
12. Four types of mature flowers are produced by these degenera- 
tions: (a) physiologically staminate, although the pollen may or 
may not be functional (the ovary is functionless); (6) physio- 
logically ovulate, the stamens having been completely eliminated by" 
degeneration; (c) bisporangiate, having both stamens and ovary 
functional (very rare); (d) completely sterile, having functionless 
ovary, and stamens completely eliminated. 
13. It is suggested that these degenerations may be of wide- 
spread occurrence, and probably are the cause of (a) dicliny, and 
finally dioecism, and (b) apogamy, and that (c) they favor the, 
development of successful methods of vegetative propagation. 
14. The cause of such degenerations is as yet unknown. It is 
suggested that deficient nutrition, excessive mutation, and hybridity 
bear no causal relation to degeneration, except as they may create 
physiological conditions favorable for it. 
I wish to thank Dr. J. M. Courter, Dr. C. J. CHAMBERLAIN, 
and Dr. W. J. G. Lanp for their interest and assistance throughout 
the course of this investigation. 
EwING CHRISTIAN COLLEGE 
ALLAHABAD, INDIA 
LITERATURE CITED 
1. BONNETT, JEAN, Recherches sur l’évolution des cellules-nourriciéres du 
. pollen, chez les Angiospermes. Archiv. Zellf. 7:604-722. pls. 39-45: 
jigs. 17. 1912. 
2. Dorsey, M. J., Pollen development in the grape, with special reference to 
sterility. Univ. Minn. Agric. Exper. Sta. Bull. no. 144. pp. 1-60. pls. 1-4. 
3- Fink, Bruce, Contributions to the life-history of Rumex. Minn. Bot. 
Studies, Series I, part 2, pp. 137-53. pls. 9-12. 1899. 
4. GARTNER, J., cited in Darwin’ s “Animals and eas under domestica- 
5. HorrMAnn, H., Uber Sexualitit. Bot. Zeit. 43:145-1 53, as —169. ee 
6. JEFFREY, E. C., The mutation myth. Science, N.S. 39:488-491. 19 
7. OVERTON, J. B. , Uber Parthenogenesis bei Thalictrum oa nani Wor- 
laufige Mitteilung). Ber. Deutsch. Bot. Gesells. 22:274-283. pl. 15. 1904- 
