1919] ECON^OMIC ZOOLOGY ENTOMOLOGY. 257 



"A maxinnun of 117 full-grown European corn borer larvae have b(>en taken 

 from one corn plant and 311 full-grown larvfe were dissected from a single 

 liill of corn containing four plants. The average number of larvae dissected 

 from 75 corn plants, taken at random in the same field, was 46. This is at 

 the rate of 1,050,040 larvae per acre of corn. As many as 15 were found at- 

 tacking a single ear of sweet corn. Field counts made in infested cornfields 

 slutwed that frequently as high as 100 per cent of the ears were infested. 



"The other economic plants mentioned as hosts of tlie European corn borer 

 are attacked by the insect only in the absence of corn, or as a result of 

 their nearness to corn in badly infested fields. The wild plants mentioned 

 as hosts of the insect, are attacked only in the absence of corn, and are not 

 economically important except that they serve as intermediate hosts for the 

 multiplication of the pest. 



"There are two generations of the insect each year. The nearly full-grown 

 second generation larvae pass the winter in a dormant condition within their 

 tunnels, and resume feeding witli the approach of warm weatlier in the spring. 

 They pupate about the middle of May, The pupal period lasts about 17 days, 

 and moths emerge the first week of June to deposit eggs for the first genera- 

 tion. A maximum number of 727 eggs was deposited by a single second gen- 

 eration female in life histoi'y cages, and the average number deposited by a 

 single female was 337 eggs. These eggs are deposited in masses from 5 to 

 about 50 eggs, on the undersides of the leaves of tlie host plant. The first 

 generation larvae hatch in about 7 days and reach their full growth in about 

 44 days. They pupate within their larval tunnels, and the pupal period lasts 

 about 9 days. The moths emerge about tlie middle of July and deposit eggs 

 for the second generation. A maximum number of 903 eggs was deposited by 

 a single first generation female in life history cages, with an average num- 

 ber per female of 545 eggs. The second generation larvae hatch in about 

 6 days and are nearly full grown by winter." 



The natural enemies mentioned include four tachinid parasites, namely, 

 jifasicera mi/oidca, Exorista pyste, E. niyripalpis, and Phorocera erccta, 

 reared from the larvae, and two liymenopterous parasites, namely, (Pmipla) 

 Epiurus ptvrophori and {Ivkiicumon) Amblytclcs hrccicinctor, from the 

 pupae. The percentage of parasitism by any of these species is very small. 



" Burning the plants containing the overwintering larvae, any time during 

 the period from the middle of October to the middle of the next May, is the 

 most effective control method now known. Other methods, applicable under 

 certain conditions, for destroying infested plants are placing in manure or 

 compost, in a silo, burying deeply in the soil, or feeding directly to live stock, 

 preferably shredded or chopped fine." 



The European corn borer problem, D. J. Caffuey {Jour. Econ. Ent., 12 

 (1919), No. 1, pp. 92-105). — This account is based upon data presented in the 

 bulletin above noted. 



The European corn borer: A menace to the countiy's corn crop, D. J. 

 Caffuky {U. S. Dcpt. Agr., Farmers' Bui. 1046 (19W), pp. 28, fifi'i. i7).— This 

 is a popular summary of ini'orniation based on llie investigations I'eported 

 in the bulletin note<l above. 



A new species of Bucculatrix injurious to hollyliock, A. Busck (Proc. 

 Ent. Soc. Wash., 21 (1919), No. 5, pp. 109, 110). — Bucculatrix althcea, which 

 appears to do considerable damage to hollyhock in California by skeletonizing 

 the leaves, is described as new. 



Two Microlepidoptera injurious to strawberry, A. Busck (Proc. Ent. Soc. 

 Wash., 21 (1919), No. 3, pp. 52, 58). — Tortricodes fragariana, which breeds 



