102 



NEW YORK STATE MUSEUM 



It is then much darker in color, being rather dark brown with 

 well marked segments, a minute head and the posterior extremity 

 truncate. The general appearance of the larva is shown at 

 figure 1. 



Fig. 1 Psilnrosae:.^ male fly , ? female fly: lateral view ; a, antenna of male ; ft, full grown 

 larva, lateral view ; c, spiracles of same ; d. anal e^-tremity from the end ; e, pupariiim ; /, young 

 larva; ff, anal segment from side — flies, young and mature larva, and pupwrium, eight tim< s naturJ 

 size ; other portions more enlarged. (After Chittenden, U. S. Dep't Agric. div. ent. Bui. 33, n. s. 

 1902) 



Natural enemies. Very little has been recorded concerning the 

 natural enemies of this species. Curtis found a small four 

 winged fly which he described as Alysia apii and presumed 

 was a natural enemy of this pest. 



Remedial measures. This species, like others which exist under 

 ground, is difficult to control with insecticides, and our principal 

 dependence must therefore be based on cultural methods which 

 may serve to avert attack. 



The standard kerosene emulsion, 1 part to 10 of water, may be 

 sprayed along carrot rows with knapsack or other sprayer. Sand, 

 land plaster or ashes, with which kerosene has been mixed at the 

 rate of y^ pint to 3 gallons, may be sprinkled along the rows. 

 These, with the exception of crude carbolic acid, a pint in 5 

 gallons, are about the only substances which have given good 

 results. Dr Fletcher states that in Canada one or the other of 

 these applications should be made weekly during June from the 

 time the roots begin to form, and particularly after the rows have 

 been thinned. 



Late sowing has also been practised to great advantage, and a 

 number of persons have found it to be of considerable value. 



