June, 1911.] Pollination Notes. 3^3 



and pistil is interesting as they were found in every case to be on 

 the upper side of the fused corolla-tube so that an insect of similar 

 proportions to a Bombus would be effectual in cross-pollination. 

 Visitors: Diptcra; Mesogramma geminata; Coleoptera; Stri go- 

 derma arboricola; Hymcnoptera; Pollstes paUipes, 

 Microbembex monodonta, Chorion caeruleum, 

 Spharophtalma ferruginata, Agapostemon radia- 

 tus. 



Family Labiatae (Mint Family). 



Monarda fistulosa. (Wild Bergamot). 



Visitors: Lepidoptcra; Hemaris diffinis; Hymenoptera; Bom- 

 bus separatus, Agapostemon splendens, Apathus 

 ciirans, Cetrania dupla. 



Nepeta cataria. (Catnip). 



Visitors: Diptcra; Eristalis tenax, Mesograpta marginata; 

 Lepidoptcra; Pieris rapae, Chrysophanus hypo- 

 phlaeas; Coleoptera; Trichius pigcr; Hymenop- 

 tera; Ccratina dupla, Elis plumipcs, Microbembex 

 monodonta, Coclioxys S-dentata, Mcgachile pru- 

 ina, and Mcgachile sp. 



Pontederiaceae (Pickerelweed Family). 



Pontederia cordata. Here we have an example of a tri-mor- 

 phous flower. Apparently no observations had been made on this 

 plant, as Knuth made no record of such. On this account special 

 care was taken in collecting and labeling the various visitors. 

 During the collecting it was noted that a bee-fly (Eristalis fiavipes) 

 visited about sixty individual flowers, on several spikes, during 

 a one-minute period. 



Visitors: Diptcra; Helophilus chrysostomus, Eristalis ft auipes; 

 Lepidoptcra; Hemaris thisba, Papilio polyxcnes, 

 Pieris rapae; Coleoptera; Megilia maculata, 

 Strigoderma arboricola, Disonycha pennsyhanica, 

 Trirhabda tomcntosa; Hymenoptera; Bombus 

 virginicus, Agapostemon splendens, Agapostemon 

 radiatus, Mcgachile (several species unidentified) 



In the above list of plants studied we have seen various types of 

 pollination, in fact, hardly two of the families show any close 

 similarity. Many more collections might have been inade on 

 the plants studied, as well as others of the same vicinity, but time 

 would not pennit. Insects laden with pollen and others who 

 sought only nectar were observed but no special studies were 

 made of these. It is the chief aim of this paper to emphasize the 

 broadness of this field of work on Cedar Point and, possibly, to 

 bring the subject to the attention of some one who can add or 

 encourage succeeding chapters on this subject for the Naturalist. 



