1909] (iraenichcr, Wisconsin Flowers and Their Pollination. 39 



centage of short tongues of the entire anthophilous insect-fauna 

 of that region i 

 unable to state. 



of that region in connection with the more southern latitude I am 



BUTTERFLIES AND MOTHS (LEPIDOPTERA). 



These insects figure as visitors to all of the flowers studied, ex- 

 cept Erigeron canadensis, and Chrysanthemum leucanthcmum. 

 The number of species of these visitors ranges from i in Erigeron 

 annuus, Cacalia reniformis, and Senecio aurea up to 25 in Soli- 

 dago gramini folia. They were observed to the number of 10 or 

 more on the following flowers : 



Tube leng-th 1 mm. Eupatoriuni perfoliatum (white), 10 Lepidoptera 



" " iy 3 mm. Aster furcatus (white), 10 



" " 1 1/0 mm. Solidago graminifolia (yellow) 25 " 



" " iy 2 mm. Cirsium arvense (purple), 11 



" " 3 mm. Aster punier us (blue), 13 



" " 4 mm. Aster novce-anglice (purple), 13 



" " 414mm. Helianthus strumosus (yellow), 10 " 



" " 4% mm. Eupatorivin purpureum (purple), 23 " 



" " 5 mm. Liotris spicata (purple). 10 



" " 6 mm. Cirsium altissimum (purple), 10 " 



2 of these species have white, 2 yellow, 1 blue and 5 purple 

 flowers. The Lepidoptera have, as a rule long, and very slender 

 tongues, and accordingly favor long, and tubular flowers. To- 

 gether with an increase in tube length in the flowers of the Com- 

 positse we witness an increase in the number of flowers of red 

 (purple) color, and these are usually visited by a greater percent- 

 age of long-tongued insects, butterflies and moths as well as long- 

 tongued bees and flies. Judging from the evidence offered by our 

 Composite there is nothing to indicate that the butterflies and 

 moths show a preference for any of these flowers on account of 

 its color. The greatest number (25) of such visitors is recorded 

 (see above) for Solidago graminifolia a species with yellow flow- 

 ers, next comes the purple-flowered Eupatoriuni purpureum with 

 23 Lepidoptera, and then follow Aster novce-anglice with purple 

 flowers, and Aster ptiniceus with blue flowers, each of these species 

 having 13 such visitors according to my lists. In Solidago gramini- 

 folia the flowers are fragrant to such an extent that in some parts 

 of the country the plant is known under the name of "sweet- 

 scented goldenrod." These flowers are very attractive to insects, 

 and most decidedlv so to butterflies and moths. 



