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The Curraxt Fruit Fly. 193 



tions. The owner informed us that several years ago he had 

 about 50 currant and gooseberry bushes, but as his entire crop 

 had been maggoty for years, he had pulled up and burned all 

 except the two Chautauqua bushes. In all probability, this 

 accounts for the abundance of the pest and the numerous egg 

 cavities in the fruit. 



Premature Ripening. 



A green currant which had been "stung" repeatedly at 8 

 A. M., showed indications of red or premature ripening at 6 

 P. M. A green currant in which one egg w^as deposited showed 

 a patch of red at the region of the egg chamber two days after 

 oviposition (Fig. 15, B). When tw^o eggs were deposited in a 

 green berry, two patches of red appeared (Fig. 15, A.). When 

 a little pressure was exerted on a prematurely ripened, white 

 currant, in wdiich an egg had been laid four days previously, a 

 small drop of liquid exuded from the mouth of the egg receptacle. 

 Wild gooseberries also show evidence of premature ripening 

 when they are punctured by the pest. A wild gooseberry in 

 which an egg was deposited, turned red at the region of the egg 

 cavity three days after oviposition had taken place. 



An attempt was made to determine whether or not the fruit 

 fly injects into the egg chamber, a secretion which causes pre- 

 mature ripening. Although many specimens were observed 

 during the process of egg-laying under a binocular microscope,' 

 no liquid was noticed leaving the opening near the end of the 

 ovipositor and entering the egg cavity. As already stated, the 

 membrane betw^een the egg-laying organ and the seventh tube- 

 like segment becomes swollen at the end of each thrust of the 

 ovipositor. However, a small amount of clear secretion ejected 

 with each thrust of the piercing apparatus probably could not 

 be seen passing from the opening of the ovipositor into the egg 

 receptacle. 



Mortality of Eggs and Larvae. 



A mortality occurs among the eggs and larvae. The per- 

 centage of mortality occurring among eggs and larvae in the 

 egg chambers of gooseberries picked on July 14, from two bushes 

 growing in the sunshine was 36 and 48 per cent. The percent- 



