The Pests of Garden Plants 



feeding, and sometimes works fearful havoc amongst Carrots and 

 Parsnips. 



Celery Fly. The apparent blisters in Celery leaves are spots 

 deficient of leaf-green, which the larva of the Celery Fly has eaten. 

 Dusting newly-planted Celery with lime or soot may do something 

 to prevent the fly from laying its eggs, but the most certain preven- 

 tive is to boil half a pound of coal tar in one gallon of water for 

 twenty minutes, add fifty gallons of clear water, and syringe the 

 plants about noon once or twice from the middle to the end of June. 

 When once the grub has made a home, it should be crushed 



by pinching the leaf between 

 the finger and thumb, or the 

 injured portions of the leaves 

 should be cut out and burned. 

 In doing this it must always 

 be remembered that the leaves 

 are as much needed by the 

 plant as the roots, and every 

 leaf removed tends to diminish 

 the vigour of the plant. Our 

 illustration shows the Celery 



Fly ( Tephritis onopordinis, Fab.) natural size and magnified. This fly 

 is also destructive to the leaves of Parsnips, and is called onopordinis 

 from its habit of frequenting the Cotton Thistle (Onopordon Acan- 

 thium}. The larva is pale green, the fly is shining tawny. An 

 Ichneumon Fly detects the larva of the Celery Fly in the Celery and 

 Parsnip leaves, and lays its eggs in the body of the larva. These 



parasites, named Alysia Apii, 

 assist in reducing the numbers of 

 the Celery Fly. A second insect, 

 named Pachylarthrus smarag- 

 dinus, is also frequently destruc- 

 tive to the pupae of the Celery 

 and Parsnip Fly. 



CELERY FLY AND LARVA 



Tephritis onopordinis 



ONION FLY AND LARVA 

 A nthomyia. ceparum 



Onion Fly. Onion crops 

 are sometimes totally destroyed 



by the larvae of the Onion Fly, here illustrated, with the perfect insect, 

 natural size and magnified. The flies lay eggs in the Onion, close 

 to the earth, and when these eggs are hatched the larvae emerge, eat 



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