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INTERSEXES IN PLANTAGO LANCEOLATA 
A. B. Stout 
(WITH PLATES XII, XIII) 
Through the resent researches of GOLDSCHMIDT (11, 12, 13), 
Banta (1), WHITMAN, RIDDLE, and their associates (see especially 
summaries by RIDDLE 22, 23), and LILiie (17, 18), the facts of 
intersexualism have acquired a significance which must be con- 
sidered by any theory of sexuality and sex determination. ‘These 
new studies show that in widely separated groups of animals which 
are usually dioecious various grades and degrees of maleness and 
femaleness in a single individual are common. Judged as entire 
individuals, such ‘‘intersexes’’ or ‘‘sex intergrades” may be pre- 
dominately male or female, or there may be various grades in the 
relative development of maleness and femaleness, giving in some 
cases at least functional hermaphrodites. Along with these there 
may be individuals that are only male or female. An individual 
sex organ may start development as of one sex and change to the 
other, or there may be a decidedly simultaneous development of 
male and female sex organs, as in the fully functional hermaph- 
rodite. The more remote secondary sex characters also exhibit 
characteristics of maleness, femaleness, or various grades of 
modifications that are intermediate. 
Such development of intersexuality in forms usually consid- 
ered as dioecious is evidence that even in dioecious forms sex is 
not necessarily determined at fertilization, and that sex is not 
alternative and irreversible for an individual or even for a sex 
organ. The data are particularly suggestive of the probability 
that sex differentiation in dioecious forms and in hermaphrodite 
forms is essentially the same process, and thus that sex determi- 
nation is on the same fundamental basis in both plants (which 
are prevailingly hermaphrodite) and animals (which are prevail- 
ingly dioecious). 
In plants the most intimate association of the two sporophytic 
sex organs is seen in the so-called perfect flowers. The opposite 
t09] [Botanical Gazette, vol. 68 
