116 HALNE STATE COLLEGE 



truded ovipositor shows that it turns backward at right angles near 

 the end, so that the egg is inserted at an acute angle backwards to 

 the position of the last segment of the abdomen during the deposi- 

 tion. An examination of Plate I, Fig. 9, which shows the pro- 

 truded ovipositor will make this plain. The end of the egg oppo- 

 site, the pedicel is the one inserted first as shown by the 

 eggs in the oviducts and the position of the deposited egg to the 

 puncture. It is from this end that the larva emerges. We have in 

 this species another instance of deposition of the egg under the skin 

 of the fruit by means of a sharp ovipositor, as in Trypeta po?noneUa, 

 Walsh. 



Egg Lavlxg Period. 

 The eggs are laid one in a place occupying about five minutes for 

 the deposition. The insects are capable of laying fully 200 eggs. 

 The time they are on the wing is about three weeks. This would re- 

 quire that several be deposited each day. An examination of the 

 ovaries showed that about two eggs of each chain or about twenty 

 were practically perfectly developed. The short life period would 

 require rapid maturation of the eggs. If ten were laid each day three 

 weeks would be required to complete ovulation. They may be de- 

 posited even faster than this. 



The Flies Slxgle Brooded. 

 Specimens of the pupae taken from the ground under the bushes, 

 about the time the currants were mature, remained in the ground in 

 a warm room all winter but did not emerge until April. Those in 

 nature emerged about June 1st. The insect therefore spends about 

 eleven months of the year in the ground. 



How Long Does It Take the Larvae to Mature. 

 The larvae began to emerge June 20th. An examination of many 

 currants at that date showed that quite a per cent contained full 

 grown larvae. The deposition of eggs began about June first which 

 would indicate three weeks as the time required for full growth. As we 

 found at this date larvae from two mm. to seven mm. in length it 

 would extend the time that the fruit is infested from the laying of 

 the first eggs to the maturity of those last laid which would be fully 

 six weeks. Our observations indicate that the larvae do not leave 

 the fruit as soon as matured which would extend the time still 

 farther. We had some larva pupate as late as July 15th. 



.Nature of the Work of the Larvae. 



When hatched the larva is about one mm. long and as soon as it 

 emerges from the egg begins to travel, often leaving a delicate light 

 colored trail close under the skin which can be seen through it. This 

 is not always the case. After traversing from a third to a half the 

 distance around the currant it locates, entering in most cases one of 



