1909] Oraenicher, Wisconsin Flotcers and Their Pollination. 59» 



380; 383; 384; 385; 386; 387; 388; 389; 391; 392; 393; 395; 413; 434; 

 442 ; 44ii ; 444— all s. or f. p. 



Beetles: 519; 522; 527 — all s. or f. p. 



Bugs: 541; 543; 544; 545; 546; 549; 553; 554— all s. 



' Eutrop 15 = 11.1% 



Hemitrop 68 = 50.4% 



Allotrop 52 = 38.5% 



Erigeron L. 



Three species are treated in this paper, which differ consider- 

 ably among each other in the characters of their flowers. E. cana- 

 densis is remarkable for the inconspicuousness, and small size of 

 its flowers, being the only species among the Compositae studied,, 

 in which not a single long-tongued bee was noticed as a visitor. 

 E. annuus has white-rayed heads with longer tubes than the spe- 

 cies just mentioned, and E. philadclphicus with its rose-colored 

 rays possesses the longest tubes of the three. 



17. Erigeron canadensis L. Horse-weed. 



This was seen blooming from July 21 to November 5. Kirch- 

 ner 2J has furnished a description of the floral characters based on 

 his study of plants growing in Germany. The heads of the plants 

 examined w.ere smaller than those observed by Kirchner, being 

 4 mm. long, and 2 mm. wide. They are surrounded by a circle of 

 very small ray florets, the erect white rays of which are only 3/h 

 mm. long, and therefore hardly noticeable even at a very short 

 distance. In the light yellow disk floret the corolla has 4 short 

 lobes, and its upper bell-shaped part is only y 2 mm. long and %. 

 mm. wide. The sweetish odor is very faint, but when these flow- 

 ers grow together in profusion they are to some extent attractive 

 to insects. Nearly all of the 58 insects of the list were observed at 

 Cedar Lake, Washington Co., Wis., and only a few at Milwaukee. 

 It is noteworthy that the Chalcid-flies Perilampus cyaneus and P. 

 hyalvnus seem to have a certain preference for these flowers 

 They were regular attendants, day after day, at Cedar Lake, and 

 were also present at Milwaukee. 



HEMITEOPOUS. 



Bees: 99, male. s. ; 102, male, s. ; 104, male, s. ; 107, male, s. ; 

 109, female, s. ; 112, female, s. and c. p.; 113, male and female, s. ; J 14, 

 male and female, s. ; 115, male, s. ; 118, female, s. ; 119; female, s. and 



29) O. Kirchner. Beitraege zur Biologie der Blueten, p. 65. 



