316 



THE STUDY OF INSECTS 



through the fruit. Early maturing varieties of apples are especially 

 attacked. When full-grown the larva goes into the ground to transform 

 where it hibernates in a brownish puparium. 



The cherry-fruit flies, Rhagoletis 

 cingulata and Rhagoletis fausta. — 

 These two species, which are closely 

 allied to the apple-maggot, infest 

 cherries. 



The currant-fruit fly, Epbckra can- 

 adensis. — The larva of this species 

 is a small white maggot which feeds 

 within currants and gooseberries. The 

 infested fruit colors prematurely and 

 usually falls to the ground. 



The Mediterranean fruit-fly, Ceratitis 

 capitata, a cosmopolitan pest, has lately 

 been discovered over a wide area in 

 Florida. It is about the size of a 

 housefly, yellowish in general color, and 

 infests a multitude of fruits especially 

 the citrus and stone fruits. The fly 

 is a most serious pest in tropical and 

 subtropical countries but will probably 

 not prove of great economic importance 

 in the northern portions of the United 

 States. 



The melon-fly, Bactrocera cucurbitce, 

 is another fruit-fly of Asiatic origin and 



Fig. 550. — The applc-maceot: i, larva; 2, • tt tj. j. 1 



puparium; ,, adult; la, head of larva from side, nOW present in Hawaii. It attacks 



feMi^ftKebwj^'SdrS^ melons - squashes, and other cucurbits in 

 larva. a very destruc- 



tive manner. 

 The round goldenrod gall. — One of the 

 most familiar of abnormal growths on plants 

 is a ball-like enlargement of the stem of gold- 

 enrod (Fig. 560). This is caused by a maggot, 

 which lives within it, and which develops into a 

 pretty fly with banded wings; this is Eurosta 

 soliddginis. The larva hibernates in the gall ; the 

 adult emerges in May. 



The round gold- 



Family PlOPHILID^E 



This family includes only a few species of small flies, rarely exceeding 

 £ of an inch in length. They are usually glistening black or slightly 

 bluish-metallic in luster. They are found about either decaying organic 

 matter, preserved meats, or cheese. The best-known species is the follow- 

 ing. 



The cheese-maggot, Piophila casei. — This fly lays its eggs on cheese, 

 ham, and bacon. The larvae live in these substances and are often serious 

 pests. They are commonly known as " skippers " on account of the re- 

 markable leaps they can make. This is accomplished by first bringing 



