16 
BULLETIN OF WISCONSIN NATURAL HISTORY SOCIETY. VOL. 5, NO. 1. 
13. Unifoliiini Canadense, May 27 — June 21. 
14. Vagnera racemosa, June 2 — June 29. 
15. Vagnera tri folia, June 3 and June 5. 
16. Clintonia borealis, June 3 and June 5. 
17. Salomonia conimutata, June 7 — July 3. 
18. Tofieldia glutinosa, June 15 — July 18. 
19. Allium Canadense, June 19 — July 17. 
20. Lilium umbellatum, June 20 — July 16. 
21. Lilium Canadense, July 2 — July 28. 
22. Allium tricoccum, July 11 — August 15. 
23. Allium cernuum, July 15 — August 29. 
In the early part of April the season of our entomophilous 
flora is ushered in by the appearance of the small-flowered and 
low-stemmed Trillium nivale, and from this time on there is a 
gradual increase in the number of the above named species in 
blossom until about May 27, when ten species have their flowers 
open together. After this maximum has been reached a gradual 
decrease in the number sets in until around the middle of July, 
when Allimn cernuum, the latest of our native species, makes its 
appearance. The maximum just referred to corresponds with the 
maximum of the spring group of Andrenine bees ( i ) at the end 
of May and the beginning of June. By consulting the lists of 
visitors appearing further on in the account given of the pollina- 
tion of the respective flowers we find that a number of the species 
representing the maximum of the spring group of those short- 
tongued bees appear as visitors of Uvularia grandiflora, Vagnera 
stellata, V. racemosa and Streptopus roseiis, all of them in blossom 
at the beginning of June. 
In the following table the flowers are placed in the classes 
of entomophilous flowers, as proposed by Hermann Mueller (2), 
and the number of insect visitors representing the different types 
is given. 
1. S. Graenieher. The relations of the Audrenine bees to the en- 
tomophilous flora of Milwaukee County. Trans. Wis. Acad. Sc. A. and 
L. Vol. XV. Parti, pp. 92-93— (1905). 
2. Herman Mueller. Alpenblumen, pp. 479-511. 
