THE LESSER HOUSE-FLY 



and insects. Nasal myiasis in man is due to species of 

 this genus. The eggs frequently hatch in the female's 

 body, so that she lays living larvae. 



ANTHOMYID^E 



This is a large family of inconspicuously colored, small 

 to moderately large flies. The squamae are usually of 

 considerable size. The larvae have four rows of thread- 

 like processes on the segments. The common Radish- 

 worm is the larva of Anthomyia radicum. The larva of 

 Phorbia fusciccps is a general feeder in roots of cabbage, 

 radish, onions, seed corn, and the like. It is an importa- 

 tion from Europe, first noted in this country in 1856. 

 The common Cabbage-maggot is the larva of Phorbia 

 brassicce, which also attacks cauliflower and radishes. 

 Just as the plants are commencing to make a good growth, 

 they suddenly wilt and die although not cut off as by a 

 Noctuid larva. -Old cabbage stumps should not be allowed 

 to stay in the garden, as they harbor late-generation 

 larvae and overwintering pupae. A troublesome pest in 

 onion bulbs is the Imported Onion-maggot (Phorbia 

 cepetorum), although the native Phorbia ceparum does 

 some damage (Ch&topsis cenea of the Ortalidas is another 

 onion maggot). The larvae of Phorbia rubivora girdle 

 the inner bark of the tips of young raspberry and black- 

 berry shoots. The larvae of Pegomyia vicina make tortu- 

 ous mines and large blotches in the leaves of beet and 

 spinach. Pupation takes place in loose soil or under fallen 

 leaves. Chittenden notes that "in many cases infestation 

 can be traced directly to the insect having bred in lambs- 

 quarters and similar weeds." Ophyra leucostoma breeds in 

 excrement. 



Especially in May and June this, at 

 Homalomyia firgt gi h( . gmall edition of Musca domestica 

 camcularis 



is sometimes abundant in houses. Those 



who do not know that insects do not grow after getting 

 functional wings believe them to be the young of the larger 

 and more common insect. However, all the veins run 

 without sharp bends to the margins of the wings. The 



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