151 
CRYPTOSTEMMA CALENDU LA0EUM 11. Br. 
During the process, all the extended styles receive considerable blows, 
and at once curve towards the bee, leaving behind upon its hairy body a 
large proportion of their covering of pollen. 
The bee, Apis mellifica, Linn., var. caffra, is the most frequent visitor, at 
least in the Stellenbosch district. Though other insects, chiefly Diptera and 
Lepidoptera, are occasionally seen on the inflorescences, on observing the pro- 
portionate number and movements of bees, it is obvious that they are the 
important insects in cross pollination. The completely effective manner in 
which bees remove the pollen is very noteworthy: as early as noon, those 
styles which elongated in the morning bear only a few scattered pollen grains, 
the style heads appearing black owing to the exposure of the dark coloured 
epidermal cells. 
If inflorescences are protected from the visits of bees, the style heads 
remain loaded with pollen throughout the day, and also during the subsequent 
changes mentioned below. 
Towards 4.30 p.m., in plants growing under natural conditions, the style 
stalk begins to contract, drawing the style head towards, and usually partly 
within, the staminal tube (Fig. 6). 
In florets in which the style or the staminal tube has been slightly dis- 
placed, the bulky style head fails to enter the tube, and engaging with the 
stamen tips, pulls down the entire tube into the bell of the corolla. Owing to 
the continued contraction of the style, considerable curvature of the filaments 
is thus caused. 
Such a condition is frequent after very windy days. Normally, however, 
the style contracts until only half the style head, or less, is projecting from the 
anther tube, in which condition it remains throughout the subsequent exposure 
of the stigmatic surface by the diverging of the very short style branches 
(Fig. 7). Before retraction is quite complete, the inflorescence closes, usually 
about 5 p.m., the ray-florets assuming a vertical position. 
During the retraction of the style, in inflorescences protected from the 
visits of bees, the pollen is scraped off the style head by the top of the staminal 
tube, and collects in a mass upon the upper part of the style. This pollen 
would bring about self-pollination in the absence of insect visitors. 
After all the florets of an inflorescence have opened (which may take two 
or three days, depending upon the size of the inflorescence and the weathei 
experienced), the entire inflorescence droops and the ray-florets wither. The 
pendent position of the flower-head is maintained until the fruits are iipe, 
when the peduncle again straightens, the involucral bracts open, and flu 
fruits, which are covered with tangled brown hairs, are dispersed b\ flu 
wind. 
Pollen presentation was also observed in Arctotheca repens, Wend ., a 
monotypic genus, frequently found growing along with 6 ryptostemina, am 
12—2 
