JAN. 1907. WISCONSIN FLOWERS AND THEIR POLLINATION. 
43 
visiting such a flower in search of food was a small bee, a male 
Ceratina dupla Say. Some bees, especially the males of solitary 
bees are in the habit of selecting flowers of convenient structure 
as lodging-places for the night or in inclement weather, and under 
these circumstances they may be instrumental in effecting pollina- 
tion. On a very windy day I found a male of the same bee 
referred to above seeking protection in one of the flowers, and on 
another occasion T saw two males of Andrena geranii Rob., taking 
up their abode in such a flower, also on account of the very high 
wind. Miss Carter kept flowers of this species under observation 
at the Botanical Garden of South Hadley, Mass., and she men- 
tions the visits of pollen-collecting honey-bees, (an introduced 
species), but not of any of our native insects. From all these 
facts I am forced to believe that spontaneous self-pollination is 
the rule in Trillium grandiiloriim and that only a small percentage 
of the flowers becomes cross-pollinated. 
Trillium nivale Riddell. Early Wake-robin. 
On a former occasion (23) I mentioned this species as being 
the earliest among our entomophilous flowers. The first flowers 
may be expected within the first two weeks in April, and in the 
exceedingly early spring of 1898 they appeared already on 
March 26. Neither before nor since the publication of the paper 
just cited have I ever succeeded in witnessing the visit of any 
insect to this pollen-flower, and spontaneous self-pollination is 
to all appearances the usual mode of pollination in our region. 
This is brought about by the recurving of the style until the 
stigma meets the anthers, but it takes place rather late, and this 
circumstance, together with the fact that the sigmas are at first 
situated above the anthers, points to cross-pollination as a possible 
outcome during the early life of the flower. 
Trillium erectum L. Ill-scented Wake-robin, 
This species has been noticed in blossom from May 19 to 
June T, but my observations do not cover its entire flowering 
period. It is of especial interest on account of the variation in 
color shown throughout its range. According to Britton's Manual 
the petals may be dark purple, pink, yellow, greenish or white. 
23. S. Graenieher. Bull. Wis. Nat. Hist. Soc., Vol, I (new series), 
pp. 1-2, 
