75 
all powerful and will only be noticed on approaching the nose 
very near to the disc of the flower. The smell comes from the 
column and in the male flower very distinctly from the anthers 
or the lodges in which they are implanted, and certainly it 
attracts flies to them. In several instances I saw flies approach 
the male flower and fly directly into the infradiscoidal groove 
without hesitation and without sitting down upon other parts 
of the corolla. In the female flowers I was not able to make a 
corresponding clear observation. Many flies visited them, but 
they wandered about upon the disc and the column indiscrimi- 
nately, apparently without giving any part of it a special pre- 
ference. On the 29/4 I observed a male and a female flower, 
growing only a couple of metres distant from each other (in- 
stances 3 and 4 in growing place A) and several times I saw 
a fly coming out from the one flower and directly entering the 
other one. The flies I observed were of two kinds, a larger one, 
1 cM. long, of green, metallic colour, and a very small one, 2 
to 3 mM. long, very frail, pink and grey in colour. Watching 
the play of the flies in the flowers I was struck by an idea 
that possibly can explain to us the significance of the ramenta 
and the white patches of the diaphragm, a problem that had 
often risen in my mind. I practically: never saw a fly sit down 
upon the ramenta, or if it did so it quickly left them again, 
and I absolutely never saw one settle down on the underside 
of the diaphragm. Are not the ramenta meant to prevent the 
flies from alighting and wandering upon the walls of the sub- 
diaphragmatical cavity, where they are of no use, and do not 
the small, stiff hairs, that cover the greater part of the column 
share in this function, compelling the insects to go straight 
to the smooth and easy highways, that are leading to the an- 
thers, where work has to be done? And have not the white 
patches a similar function? In the relative darkness, that reigns 
in the interior of the flower, these large, white spots gid shining 
like diabolical eyes, which readily might fill a fly's mind with 
fear, keep him away from the higher regions and make him 
hide under the protecting cover of the disc. 
