148 MASS. EXPERIMENT STATION BULLETIN 178. 



Description of the Insect. 



When full grown the larva is 1 inch in length; the body is flesh-colored, 

 often somewhat smoky or reddish above, while the head is flat and dark 

 brown in color. On close observation a transverse row of four hght 

 colored spots, with two smaller ones immediately behind them, can be 

 seen on each abdominal segment. From each of these light colored areas 

 a short, stout spine arises, and this character distinguishes the European 

 com borer from the mature caterpillar of the potato and corn stalk borer 

 (Papaipema nitella Gn.). 



The female moth has a robust body, is pale yellow in color and has a 

 wing expanse of a little over 1 inch. The outer third of the fore wing is 

 traversed by two serrated lines darker than the rest of the wing, while the 

 hind wings are light yellow in color. 



The male moth has a long, slender body, is slightly smaller in wing ex- 

 panse, and in color is reddish brown, being much darker than the female. 

 Between the two serrated lines mentioned above is a pale yellow streak, 

 and near the middle of the fore wing are two small yellowish spots. The 

 hind wings are grayish and crossed by a broad band of pale yellow. 



European History. 



Pyrausta nubilalis is widely distributed in Europe and Asia, having 

 been reported in literature as occurring in Central and Southern Europe, 

 West Central and Northern Asia and Japan. Its food plants in these 

 widely separated localities consist of corn (except fodder corn), hemp, 

 hops, millet and several wild grasses. Corn and hop plants are severely 

 damaged by this pest, 50 per cent, of these crops being destroyed in some 

 sections of Central Europe. 



Foreign literature contains a large number of references to the serious 

 damage caused by the larvse of P. nubilalis, but there is a decided lack of 

 literature dealing with its biology and control. 



Status of the Pest in Eastern Massachusetts. 

 Importation. 



The questions naturally arise as to how, when and where the European 

 com borer was introduced. At the present time these cannot be definitely 

 answered, but a few deductive conjectures may be given. 



The important European food plants of P. nubilalis consist of corn, 

 hemp, hops and millet. Of these the only food plant offering ideal condi- 

 tions for its importation is hemp. This crop is grown to some extent in 

 Southern Europe, and probably some plants hifested by larvffi of P. 

 nubilalis were cut and shipped during the fall and winter months to a 

 cordage company in the vicinity of Boston, Mass. These plants were not 

 used immediately, and the larvse transformed to pupse in early spring, 

 and soon emerged as moths. On finding corn plants growing in the 



