486 Bulletin 78. 



from maggots which were mining in the leaves of beets. This is the only 

 well-authenticated instance of the pest attacking other than Cruciferous 

 plants. This leaf-mining habit of the insect seems not so improbable, how- 

 ever, when it is known that in 1878, Dr. Riley found the maggots burrowing 

 in the stout mid-ribs of cabbage leaves in the summer ; and Mr. Fletcher has 

 recorded, in 1891, the pest as mining in the mid-ribs and boring through the 

 heads of winter cabbages in storehouses. 



Breeding experiments here at the insectary have developed further con- 

 firmatory evidence in support of some of the conclusions to be drawn from 

 the above account of the recorded food-plants of this pest. And these exper- 

 iments have also revealed several new food-plants of the insect, which will 

 throw new light on its habits and life-history ; and which are of considerable 

 importance in connection with the methods to be used in combating the 

 pest. 



In 1891, maggots ruined a field of turnips at Ithaca ; the insect was bred at 

 the time, and it proves to be the Cabbage Root Maggot. -This year several 

 turnips and radishes were growing in an exposed bed in the insectary ; and 

 some of them were found to be attacked by maggots which produced the 

 Cabbage-fly. The pest has also been bred, in the insectary, from the buried 

 stems of seed cabbage. 



Thus the.se breeding experiments, the evidence of other observ- 

 ers, especially of Dr. Fitch and Prof. Cook recorded above, and 

 the identity of all the Cabbage and the Radish -maggots examined 

 from various parts of the country seem, to the writer, sufficient 

 proof that the Cabbage and the Radish Maggot are the same 

 insect.* 



After learning that it is the universal testimony of cabbage and radish 

 growers that the maggots do but little damage to late crops of these vegeta- 

 bles, the question at once occurred to us, has the pest other, as yet unsus- 

 pected, wild food-plants ? Naturally our attention was turned to the 

 Mustard- like weeds which are usually to be found in abundance in every 

 garden or cultivated field and along the road-sides. Therefore, in the latter 

 part of May plants of the well-known Shepherd's Purse {Capsella bursa- 

 pastoris), and of the Common Winter Cress or Yellow Rocket {Barbarea 

 vulgaris) were transplanted from the field to cages in the insectary ; and 100 

 maggots, brought from Long Island, were put about the base of each plant. 

 Three weeks later the cages were examined. The maggots had eaten freely 

 of the roots of the Bar bat ea ; but the roots of the .Shepherd's Purse showed 

 only slight indications of having been eaten, and many of the maggots had 

 failed to develop. 



* I say " ilie Cabbage and the Radish Maggot " because two other Antho- 

 myiians, A. radiann the Root Maggot, and P. fusciceps, the Fringed 

 Anthomyiian, are recorded as feeding on these vegetables ; but I believe the 

 latter rarely does, and the former not nearly so commonly as does P. brassiccB. 



