ECONOMIC ZOOLOGY ENTOMOLOGY. 555 



Nine new tropical American genera of Muscoidea, C. H. T. Townsend 

 (Insccutor Imcitiw Menstruus, 3 (1915), No. S-10, pp. 91-97). 



The Muscidae with, bloodsucking larvae, E. Roubaud (Conipt. Rend. Soc. 

 Biol. [Paris], 78 (1915), No. 5, pp. 92-97, figs. 2).—\ brief discussion of this 

 class of Diptera. 



Control of injurious aphids by ladybirds in Tidewater Virginia, D. E. 

 Fink (yirginia Truck Sta. Bui. 15 (1915), pp. 337-350, figs. 6).— Tlie introduc- 

 tion and colonization of ladybird beetles was undertalcen in Tidewater Vir- 

 ginia primarily to aid in the control of the green peach aphis on spinach. Other 

 important aphidids in the region are the cabbage aphis, the bean aphis (Aphis 

 rumicis), the pea aphis (Macrosiphum pisi), and the potato aphis (M. solani- 

 folii). Shipments of lady beetles from California to Norfolk were commenced 

 in 1910. During 1910 and 1911 several colonies of the spotted lady beetle 

 (Megilla maculata) and the convergent lady beetle (Hippodamia convcrgcns) 

 were liberated, but the largest number of colonies of the convergent lady beetle 

 were established during the years 1913 and 1914. In all 21 colonies were 

 liberated, aggregating a total of nearly 1.000,000 lady beetles. The colonies 

 were placed within a 5-mile radius of each other and were liberated during 

 the early spring. 



In this bulletin the author presents information in regard to the life history 

 and habits of these beetles, information relating to which has been previously 

 noted from another source (E. S. R., 27, p. 361). In Tidewater Virginia the 

 convergent lady beetle hibernates in proximity to the feeding areas in weeds, 

 debris, or in the ground. The spotted lady beetle hibernates on trunks and 

 stumps of oak trees. The life cycle of the lady beetle from egg to egg is said 

 to pass in approximately four to six weeks. There are five generations of the 

 lady beetles in Tidewater Virginia, and from April to the middle of July three 

 generations occur. From the middle of July to the end of August practically 

 no breeding takes place, apparently due to scarcity of food ; but from the first 

 week in September until very cold weather sets in two more generations may 

 occur, depending largely on the weather. 



The introduced lady beetles appear to have been of much value as checks to 

 sporadic outbreaks of aphidids. V^liere they were colonized no further serious 

 trouble from aphidids has been reported. 



A comparative study of a series of aphid-feeding Coccinellidae, C. P. 

 Clausen (Jour. Econ. Ent., 8 (1915), No. 5, pp. 487-^91). — The results secured 

 in the investigations here reported, conducted at the Citrus Substation at River- 

 side, Cal., have led to the following conclusions : 



" Temperature and humidity are very strong controlling factors in the 

 development and behavior of the different species. The number of eggs depos- 

 ited imder normal field conditions varies from 200 to 500, and occasionally 

 more, extending over a period of 4 to 8 weeks in case the female lives the full 

 adult life. The period intervening between emergence and mating is 1 to 3 

 days, and from mating to oviposition 8 to 11 days. A period of 10 to 15 days 

 thus intervenes between emergence and the beginning of oviposition. Ovipo- 

 sition normally takes place daily, with occasional exceptions. The number of 

 aphids eaten by the larvae of the different species varies approximately with 

 the size of the individuals, the number varying from 216 to 475 for the entire 

 larval period. The above to a somewhat lesser extent is true of the adults 

 also." 



The corn silk beetle, Luperodes varicornis, and its control, R. W. Harked 

 (Jour. Econ. Ent., 8 (1915), No. 5, pp. 507, 50S).— This beetle is reported to 

 have appeared in enormous numbers in many corn fields of several counties in 

 Mississippi, where it eats the silk just as it grows out from the ear, and while 



