E3 ARISAEMA TRIPHYLLUM 
small flies and bees without inconvenience or danger, the narrow 
space around the pistillate spike would make it quite difficult 
or impossible for the same insects, once 
in such close quarters, to escape. Ob- 
servations have proven that many in- 
sects find this a veritable death trap. 
With a view of securing some defi- 
nite basis for a possible explanation of 
the pollination question, about two 
thousand plants have been examined 
and the results with reference to insect 
visitation tabulated. Different sets of 
data have been so nearly alike in per- 
: tudinal Centage ratios, that a full account of but 
section aii ha pah of one group will be given. From 9-10 
a pistillate spike, showing the Ą.M. on a bright, warm day, May 18, 
narrow space about the flower 
cluster. Reduced about %. 
Fic. 12. Similar section and an equal number of mature pistil- 
showing EARP pen late clusters were examined. The 
IPA flowers, and —taminate spathes showed a total of 70 
spathe ze baa cies E Sea ae 
living and 73 dead insects. The pistillate 
spathes showed a total of 60 living and 557 dead insects. This set 
of observations could be duplicated many times. The following 
variations should be noted. In mid-afternoon and early evening 
few living insects are found in either staminate or pistillate spathes. 
The greatest number of insects have been found about midday of 
dark and rainy days. Insects found in staminate spathes are 
well dusted over with pollen, and many of those found in pistillate 
spathes also carry pollen on body, wings or legs. The data given 
above would seem to indicate that the insects seek the spathes for 
hiding or shelter. Those entering staminate spathes may go out 
again readily, but carry with them a load of pollen. If the second 
spathe entered surrounds a pistillate spike, the pollen will probably 
be left on the stigmas as the insect struggles to escape. This, of 
course, implies a purely accidental transfer of pollen. The fact 
that more living insects are found in pistillate spathes than in 
staminate, as well as the finding of occasional visitors feeding on 
the stigmas indicates a possible attraction of the pistillate cluster. 
100 mature staminate flower clusters 
