366 BOTANICAL GAZETTE [NOVEMBER 



bears both upon the nature of mutation and upon the real signifi- 

 cance of the "presence and absence" hypothesis. 



STRASBURGER has shown that females of Lychnis dioica attacked 

 by Ustilago molacea become pseudo-hermaphrodites through the 

 production of stamens, which however are non-functional, owing 

 to the fact that the smut produces its spores in the anthers. This 

 seems to justify his conclusion that each sex possesses some of the 

 potentialities of the opposite sex. 



The view is expressed that the sexes represent alternative 

 states which in different species may be attained in various ways, 

 through either quantitative or qualitative changes, additions, 

 subtractions, substitutions, or transformations, and that in some 

 instances the action of environment may prove effective in deter- 

 mining which of these states shall find expression. Nearly all 

 the recent investigations indicate, however, that sex is at least 

 predominantly dependent upon the genotypic nature of the indi- 

 vidual. 



CARNEGIE STATION FOR EXPERIMENTAL EVOLUTION 

 COLD SPRING HARBOR, N.Y. 



LITERATURE CITED 



1. BALTZER, F., Ueber die Grosse und Form der Chromosomen bei Seeigel- 

 eiern. Verhand. Deutsch. Zool. Gesells. 1908. 



2. BATESON, W., Mendel's principles of heredity, pp. xiv+396. Cambridge: 

 University Press. 1909. 



3. BORING, ALICE M., A small chromosome in Ascaris megalocephala. Arch, 

 f. Zellf. 4 X : 1 20-13 1. pl- T - 1909. 



4. BOVERI, T., Ueber " Gescmechtschromosomen " bei Nematoden. Arch, 

 f. Zellf. 4 1 : 132-141. jigs. 2. 1909. 



5. CASTLE, W. E., A Mendelian view of sex heredity. Science N.S. 29:395- 

 400. 1909. 



6. CORRENS, C, Die Bestimmung und Vererbung des Geschlechtes, nach 

 neuen Versuchen mit hoheren Pflanzen. pp. vii+8i. figs. p. Berlin: 

 Gebr. Borntraeger. 1907. 



7. - , Die Rolle der mannlichen Keimzellen bei der Geschlechtsbestim- 

 mung der gynodioecischen Pflanzen. Ber. Deutsch. Bot. Gesells. 26a: 

 686-701. 1908. 



8. DONCASTER, L., Sex inheritance in the moth Abraxas grossulariata and its 

 var. lacticolor. Report Evol. Comm. IV. pp. 53-57. 1908. 



