564 PROCEEDINGS OF SECTION D. 
Colocasia macrorrhiza, Sch.—The flowers in the spadix are 
unisexual, the females being in the lower part, and the males on 
the upper, and there is an intermediate space occupied by abortive 
stamens and pistils. The lower part of the spathe forms a chamber 
round the female flowers. In the first stage, the spathe and 
spadix are green, with a strong delicious scent resewbling that of 
violets. At this stage it is visited by small beetles which Rev. T. 
Blackburn has been good enough to identify for me as Brachypeplus 
Murrayi Macl., these crawl into the spathe and feed on a liquid 
exuded by the pistils. |The spathe then closes at the lower part 
round the females, so that nothing can get into the chamber. The 
upper part of the spadix turns dull orange in colour, and the free 
portion of the spathe white. The scent is now less powerful, and 
the anthers open and discharge quantities of dusty pollen. Beetles 
still visit the spathe, and become dusted with pollen ; but, failing 
to make their way into the chamber, fly off to flowers in the first 
stage, and getting into the open chamber are shut up init. In 
moving about, feeding on the liquid, or trying to get out, they 
deposit pollen on the stigmas. The beetles also eat the upper 
part of the spadix, and so are covered with pollen. When tired of 
their confinement they burrow out through the walls of the chamber. 
The leaves and spathe are attacked by the larvee of a species of 
Agaristid, which hide in the chamber, in the axils of the leaf stalks, 
or in burrows which they excavate in the thicker veins. They 
come out at night to feed, and when alarmed drop by a thread 
and hang suspended. ‘These also aid in fertilisation, as they are 
sometimes caught in the chamber, but always eat their way out 
after a time. The plants in my garden were also attacked by a 
large, very hairy larva, of a burnt sienna colour, and by the larva 
of Cherocampa Oldenlandic, which also attacked the plants of a 
taro plant close by. 
While observing the flowers of Colocasia, I took some hundreds 
of thermometer readings in and about the flowers at all stages, 
but could detect no rise of temperature. Several observers have 
noted in some species of Aroide a rise varying from 10° to 47-75" F. 
above the air temperature. 
I also made observations of the rate of growth of the flower 
stem from the time its first tip showed till it had reached the first 
flowering stage. These showed that the growth took place princi- 
pally at night. The average growth during twelve hours of day- 
light was 5 mm., while the average during the night was 12 mm. 
The maximum night growth was 17 mm., and the minimum (the 
last night) was 4 mm. On very hot days the growth was much 
slower than on cool days. The total growth in 178 hours was 
121°5 mm. 
The sheathing leaf-stalks hold a considerable quantity of water 
after rain, which remains a considerable time. In one instance 
