156 Proceedings of Indiana Academy of Science. 
below this strength of the sugar solution the pollen grew. The second 
point of interest is that the branching of the pollen tube which this plant 
showed occurred only in the 30% of cane sugar and as above noted. It will 
be seen that in 40% cane sugar the germination dropped off greatly as 
only 3 grains of pollen grew. It has been known for a long time that the 
pollen tube sometimes branches as it descends through the stigma of some 
plants. The germination of the pollen of this plant was rather slow as it 
required one-half an hour to begin. Its pollen lived in the ungerminated 
condition for eight days and it grew best in a 20% solution of the cane 
sugar. Most of the pollen experimented with in the cultures used in this 
investigation was from plants gathered in Monroe County, Indiana. Some 
of the plants were obtained from widely separated localities and where- 
ever and whenever an opportunity presented itself. Some came, for ex- 
ample, from Texas, some from Missouri, and others from Colorado which 
I gathered on Pike’s Peak and vicinity. Twelve plants from Pike’s Peak 
that I tested especially as regards their longevity, lived only ten days in 
the longest case. Some of these I did not expect would germinate under 
any conditions, whether their pollen was young or old, and this was fully 
verified by experiment. However, these plants were in every case also 
subjected to the usual investigation in order to leave no doubt on the ques- 
tion. Still others of the plants came from Dearborn County and from 
Clark County, Indiana. All of the experiments in this paper were carried 
out, as above stated, in pure distilled water and in the different strengths 
of cane sugar mentioned. The distilled water and cane sugar were as pure 
as possible. No experiments were performed or attenticn given to the 
question of additional substances, such as gelatine, added to these solu- 
tions. Considerable work also has been done in some phases of this field, 
It constitutes, however, a problem in itself and merits much more extended 
investigation than it has yet received. 
