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JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



other forms, as the striped cucumber beetle {Diahrotica vittata Fab.) 

 or the painted cucumber beetle {Diahrotica pidicornis Horn), is appar- 

 ent. In some parts of the country the corn root-worm {Diahrotica 

 duodecimpunctata Oliv.) is styled ^^the diahrotica." As a popular 

 name "the western flower beetle" is fairly satisfactory, for, while it 

 may attack the leaf, the stem or the fruit, it shows a decided preference 

 for the flowers. 



Feeding Habits. The insect feeds upon many different kinds of 

 plants; its choice depending upon the locality, the season, or the stage 

 in its life history. In the vicinity of Berkeley it feeds to some extent 

 upon more than five hundred varieties of plants and it is positively 

 harmful or highly destructive to at least one hundred of these. 



The flora of this region is especially rich; the range of plant life from 

 the crest of the Berkeley Hills to the bay is very extensive, and the 

 University of California, through the departments of Botany, Agri- 

 culture and Landscape Gardening, has introduced various forms of , 

 plants from South America, Africa, China, Japan, Australia, Ceylon, 

 Russia and other foreign countries. Counting the native plants, the 

 cultivated plants and those plants that have been introduced for experi- 

 mental and ornamental purposes they would number several thousand. 

 The following is a list of fifty of the more common and more generally 

 distributed plants upon which the soror feeds: beet, bean, pea, mar- 

 guerite, nasturtium, rose, holyhock, cucumber, pumpkin, muskmelon, 

 watermelon, poppy, alfalfa, sweet corn, potato, pepper, artichoke, 

 tobacco, radishes, mustard, clover, lettuce, eggplant, parsley, plum, 

 apple, pear, peach, cherry, currant, canna, dahlia, foxglove, dandelion, 

 pinks, peony, violet, aster, buttercup, sunflower, black-eyed-susan, 

 primrose, bleeding-heart, lily, burdock, thistle, verbena, morning- 

 glory, wistaria, dog-fennel. 



Its work on cultivated flowers is very noticeable, for it makes un- 

 sightly holes through the petals and destroys their beauty, but it is no 

 less destructive to the essential organs for it may eat the upper part of 

 the pistil (stigma), dig into the ovary or attack the anthers. Since it is 

 especially fond of pollen and nectar it can frequently be found in a 

 flower doing no apparent damage. 



By gnawing holes through the thin and tender parts of the leaves it 

 destroys the foliage and causes a loss of the sap, which is the life blood 

 of the plant, besides interfering with photosynthesis or starch making, 

 a vital process of the plant, and making a way for fungus diseases to 

 attack the injured part. 



It sometimes attacks very young cucumbers or muskmelons, the 

 pods of young beans, cauliflower, and the fruits of eggplant and even 

 tomatoes. 



