December, '16] SCIENTIFIC NOTES 571 



ble factors are the noise of the gasoline engine and the walking of the mules and oper- 

 ators of the machine through the grass, the noise and the general disturbance prob- 

 ably causing more insects to fly than would have been attracted solely by the light. 



T. E. HOLLOWAY. 



On the Distribution of the Imported Cabbage and Onion Maggots.' In recent 

 publications, e. g., one published this year,^ the authors state in regard to the imported 

 cabbage maggot, "According to published statements it has now spread through- 

 out the United States and Canada, and caused injury wherever its food plants are 

 grown. Some entomologists, however, consider this questionable and regard another 

 species, Pegomya ftisciceps Zett., which is a general feeder, as responsible for the 

 injury in the Southern Atlantic States." 



This remark requires a little elucidation. For many years entomologists and 

 others have reported the cabbage maggot and the onion maggot as occurring in Texas 

 and other Gulf States, whereas these species are not known to occur there but are 

 represented by the related seed-corn maggot {Pegomya fusciceps Zett.). This last 

 species is generally distributed in the United States, and is often concerned in injury 

 to cabbage and onion where the true cabbage maggot (Pegomya brassicoe Bouche) 

 and the important onion maggot (P. cepetorum Meade) are generally believed, or 

 have proved to be, the principal enemy. Considerable has been written on this 

 topic, and the main purpose of this note is to call attention to the fact that the true 

 cabbage maggot positively does not occur, permanently at least, south of New Jersey 

 so far as we can learn, and is somewhat limited, if not entirely so, to the more northern 

 portion of that state, if, indeed, it occurs at all south of the middle of that state. 

 From that point southward it is replaced by the seed-corn maggot which does con- 

 siderable damage to vegetables and other plants grown in that region. 



It may be remarked at this point that the imported onion maggot has about the 

 same distribution as the cabbage maggot, and when the onion maggot and the cab- 

 bage maggot are reported from the South, it is the seed-corn maggot which is actually 

 doing the damage. 



This opinion is based on specimens which have passed through the writer's hands 

 for a period of years, and have either been identified or the indentifications confirmed 

 by such authorities as CoquiUett, Walton, and F. R. Cole. The different species 

 are not so difficult to determine provided both sexes, especially the males, are properly 

 mounted. 



F. H. Chittenden, Bureau of Entomology, United Stales Department of Agriculture. 



1 Published by permission of the Secretary of Agriculture. 



2 See Britton, W. E., and Lowry, Quincy S., Insects Attacking Cabbage and 

 Allied Crops in Connecticut. Conn. Agr. Exp. Sta. Bui. No. 190, .Jan., 1916, 

 Entom. Ser., No. 23, p. 3, and others. 



