po 
a Se ae E Uy p pP y gee EEA A Ek NE een 
a S a E E R aaa a i aai e aia a a s n aae a N ate a A AEE a El A el a gee Sy ae E e 
hanana 
SEx DISTRIBUTION 39 
lying in different positions (TEXT FIG. 28a). These cells are much 
more abundant in the outer portion of the corm. In the endo- 
sperm the few raphide-bearing 
cells are similar to those in the 
corm but are smaller. In the 
walls of the ovary and maturing 
fruit the cells are chiefly in the 
upper portion, where they form a 
distinct area (PLATE 2, FIG. 26; 
TEXT FIG. 51). Probably the 
most clearly defined raphide re- 
gion is that in the root. Here, 
as described in the section on 
root structure, certain cells in 
the outer periblem are differen- 
tiated shortly above the growing Eres 4eko. “Didferent Incins of 
tip and form almost continuous raphide-bearing cells in the leaf meso- 
receptacles for long lines of raph- —Phy!l. 2 
ide bundles (PLATE 5, FIG. 65). 
Wherever found the raphide 
cells are differentiated very 
early. They rapidly increase in size, retaining their protoplas- 
mic lining and a living nucleus long after the central vacuole has 
been filled with bundles of crystals. 
Fic. 51. Raphide-bearing cells in 
the outer portion of the ovary wall. 
X 52. 
SEX DISTRIBUTION 
Although A. triphyllum is usually considered a dioecious plant, 
spikes bearing both staminate and pistillate flowers are frequently 
found. From the examination of hundreds of plants through three 
consecutive years the writer finds the ratio between staminate and 
pistillate spikes about 3:2, and 8-10 per cent. of the whole number 
mixed. The type of a mixture most often found is that of a spike 
bearing chiefly pistillate flowers and a few staminate flowers at 
the upper or lower end or at both upper and lower ends (PLATE I, 
FIG. 23; PLATE 4, FIG. 55). Usually the number of staminate flowers 
is less than shown in FIG. 55. Occasionally the ratio is reversed, 
and a spike showsa few pistillate flowers scattered through a mass of 
staminate flowers as in PLATE 4, FIG. 60. PLATE 4, FIG. 57, shows 
