WISCONSIN FLOWERS AND THEIR POLLINATION. 
II. 
By S. Graenicher. 
SAXIFRAGACE^ and GROSSULARIACE^ * 
FAM. SAXIFRAGACE^. 
Saxifraga Pennsylvanica L. Swamp Saxifrage. 
The genus Saxifraga is represented by a very large number 
of species in Europe, and for many of these their relations to 
insect visitors have been recorded, while for our North American 
species this has not been done in a single instance. The only one 
occurring in our immediate neighborhood is the species named 
above. It is fairly common in swampy grounds, and is rather 
large for a saxifrage, some specimens attaining a height of about 
I m: In the Menomonee Valley, between Milwaukee and Wau- 
watosa, the plants were seen in blossom from May 15 to June 18. 
The numerous small flowers (about 5 mm. in diameter) are 
arranged in cymes, and the latter form a long panicle on a stout 
scape. In the erect flower the .small greenish calyx-lobes are re- 
flexed, but the lanceolate white petals assume an horizontal posi- 
tion, and the 10 stamens in 2 rows are also directed laterally from 
the time on that they begin to shed their pollen. The upper por- 
tion of the ovary forms a disc-shaped nectary around the two 
styles, and nectar is secreted in abundance. These flowers are 
decidedly proterandrous, and in this respect they agree with the 
majority of the European species, very few of which are proter- 
ogynous. Dehiscence starts in the stamens belonging to the 
outer row, and a few days later those of the inner row become 
■"'•Classification and nomenclatnre according- to "Britton's Manual 
of the Flora of the Northern States and Canada." 
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