552 JOURNAL OF ECONOMIC ENTOMOLOGY • [Vol. 9 



cultivated crops that they prefer were not plentiful before the 10th 

 of June but the beetles were very much in evidence; working upon 

 cultivated flowers, ornamental shrubs and occasionally upon trees and 

 vines. During April, May and the first ten days of June they were 

 found on two hundred and eighty plants — besides the ones which they 

 commonly feed upon: spinach, kale, peas, cucumber, melon, cantelope, 

 pumpkin, beet, mustard, turnip, peanut, corn, cane and coffee-beaii, 

 they were noticed on peaches, plums and strawberries and also on such 

 plants as petunias, four-o'clocks, narcissus, wisteria, sweet-peas, jack 

 beans, catalpa, morning glories, touch-me-nots, cape jasmine, and 

 many others. While they sometimes gnawed the leaves of morning- 

 glories, wild sweet potatoes, touch-me-nots and four-o'clocks, they 

 seemed to prefer the pollen, the essential organs or the petals. 



To gain some idea of the range of their distribution on native plants 

 at one particular time an extensive trip was made through the woods 

 and fields that were in the wild state or at least as free from cultivated 

 plants as possible. On April 28 they were found on wild plants as 

 follows: Erigeron sp., Rudbeckia hirta, Cathartolinum rupestre, Aster- 

 ^acese, Medicago hispida, Allium helleri, Echinacea pallida, Hartmannia 

 .speciosa, Chenopodium album, Plantago aristata, Daucus ptisillus, Cor- 

 ■nM4 8^tolonifera, Verbena bracteosa, Vicia cracca, Lantana macropoda, 

 Ptelea mollis, Monarda fistidosa, Erythrina herbacea, Xanthoxalis 

 cornicidata, Apiace?e sp.. Verbena stricta, Smilax, Verbena officinalis, 

 Laurocerasus caroliniana, Carpinus caroliniana. 



In most instances they were working upon the flowers, usually the 

 pollen. 



Feeding Habits; Effects of Changing Food 



Some experiments in adapting them to different kinds of food were 

 tried and in every case they were able to change from an exclusive diet 

 of one kind of food to another without any more serious consequences 

 than a loss of appetite for a few days. Several kinds of plants they 

 would not eat, even after a fast of eight or ten days. 



While they will thrive on cactus blossoms the leaves of this plant do 

 not agree with them. Under ordinary conditions they will not eat 

 cactus leaves but after twenty-eight beetles had been kept without 

 food for four days a supply of cactus leaves was given to them and 

 they ate rather sparingly. In twenty-four hours eight of them were 

 dead but the remaining twenty lived sixteen days with no other food, 

 when two more died. Some of them became quite lively on this diet 

 and after twenty-two days' imprisonment began to copulate. 



It appears that the 12-punctata is not as hardy an insect as the soror. 

 It is by no means as ready to eat anything that is convenient but it 

 shows a decided ability to meet conditions of shortage in a particular 

 kind of food. 



