184 MANUAL OF VEGET ABLE-GARDEN IN^SECTS 



^3I33~JTTTII^ in a measure but the 

 ^K^^^"'"^-''^-'-*^"^---^^ Size and quality of the 



Fig. 105. — Larva of the carrot rust-fly (X 7^). 



Fig. 106. 



— Puparium of the carrot 

 rust-fly (X 9f). 



quality 

 crop are seriously im- 

 paired. In Fig. 104 are 

 shown two injured plants in comparison with a healthy one. 

 The maggots become mature in about a month. When full- 

 grown the larva is about y% 

 inch in length, pale straw- 

 colored, pointed in front with 

 the posterior end of the 

 body obliquely truncate. The 

 mouth is provided with a pair 

 of black, curved hooks with which the maggot is able to rasp 

 off portions of the tissue of the root (Fig. 105). 



When mature, the greater number of the larvae desert the 

 roots and in the surrounding soil trans- 

 form to puparia. The puparium (Fig. 

 nit^ , i^ni^^^H ^^^^^ ^^ about ^ inch in length, light 

 l^k^^^J^H^^^HI brownish in color and in shape re- 

 likmBrnKKKmi^L sembles somewhat a grain of wheat. 

 From these puparia there emerges in 

 late August a second brood of flies. 

 The insects hibernate as puparia 

 in the soil or as maggots in the 

 roots. 



It is quite probable that not all 

 the puparia of the first brood trans- 

 form the same season, but the second 

 brood of flies is often large enough to 

 produce a serious infestation of late 

 carrots and to cause appreciable 

 injury to celery in the fall. While 



Fig. 107. -A celery root in- ^^^ maggotS of the SCCOIld brOod 

 jured by rust-fly maggots f '^ 



of the second brood. burrow ill the tap-root of the celery 



