JAN. 1907. WISCONSIN FLOWERS AND THEIR POLLINATION. 
17 
Bees. 
Flies. 
Butter- 
flies. 
Other 
Insects 
Pollen-flowers — 
Trillium nivale 
" erectum 
" recurvatum. 
Vagnera racetnosa . . . . 
Unifolium Canadense. 
Flowers with exposed nectar- 
Vagnera stellata 
" trifolia , 
Tofieldia glutinosa. 
Flozvers ivith concealed nectar- 
Trillium grandifloruni 
" cernuiini 
Allium Canadense 
tricoccuni 
" ceruuum 
Bee-flowers — 
Erythronium albiduni 
'* Americanuni. 
Uvularia grandiflora 
Salomonia biflora 
" coniniutata 
Asparagus officinalis 
Streptopus roseus 
Clintonia borealis 
Biifferflv-flou 'e rs — 
Lilium umbellatum 
" Canadense.. 
18 
2 
16 
9 
12 
22 
'9 
15 
3 
1 
POLLEN FLOWKRS. 
I 
This class comprises the flowers which, on careful examination 
do not reveal a trace of nectar, and are therefore visited on 
account of their pollen only. 
Three species of Trillium figure in this class while the two 
remaining ones of our flora are nectar-producing, and are referred 
to the flowers with concealed nectar. The flowers of all of these 
species are more or less showy, and well supplied with pollen, and 
still they are so rarely visited as to cause us great surprise. The 
