28 
CECIL YAMPOLSKY 
lies which contain forms that show more than one kind of distribution of the 
sex elements. Thus in the monocotyledons ten of the eleven orders have 
hermaphroditic, monoecious, dioecious, and polygamous individuals. 
There are twenty-two families represented in the ten orders. In the dicoty- 
ledons thirty-one of the forty orders have representatives of two or more of 
the various distributions of the sex elements. There are ninety families 
that exhibit this tendency. At the end of the paper are listed the families 
and the sex forms found in each. Their distribution is further shown by 
means of a table. 
Change of Sex Apparently as a Result of Environmental Influences 
Changes of sex from year to year and apparently as a result of en- 
vironmental influences are inextricably interrelated with the fluctuations of 
maleness and femaleness in sex intergrades and must hence be briefly con- 
sidered here. 
Gallardo (1901) reports on the work of Spegazzini, who by transplanting 
wild female plants of Dioscorea, Clematis, and Trianosperma found that 
the following year fruit was set. Examination showed that these plants 
bore either male or hermaphroditic flowers besides the female flowers. 
The following year, however, they became female again. Male plants, 
transplanted, showed no change of sex. 
De Vries (1903) figures the appearance of seeds on a male branch of 
Mercurialis annua. Strasburger (1910) cut back 200 male plants to ascer- 
tain whether severe pruning would have any effect upon them. Only one 
male plant that had been cut back produced a single female flower. One 
of his plants, no. 16, started as a pure female. It began, however, gradually 
to develop male flowers with functional pollen. It became more and more 
male, producing the characteristic odor of the male plants. He collected 
55 seeds from this plant but only 5 germinated, 2 males and 3 females being 
produced. This behavior of Strasburger 's plant, with reference to the 
production of a mixed progeny, might perhaps be explained on the basis 
that the seeds set when the plant was predominantly female produced fe- 
male offspring, while the seed produced when the plant was predominantly 
male produced males. The 55 seeds may even have represented the three 
conditions, male, female, and hermaphroditic. 
Higgins (191 6) reports a case in which a male plant of Carica papaya 
was cut down, leaving only a stump. This stump sent out branches which 
bore abundant fruit. 
Pritchard (1916) found that by mutilating male and female plants of 
hemp the appearance of organs of the opposite sex could be induced. The 
author calls attention to the presence of monoecious individuals as a nor- 
mal occurrence, often constituting as high as eight percent of the dioecious 
cultures. 
Davey and Gibson (19 17) have found in Myrica, which is described as 
