378 



Insect Pests. 



The female places a single egg in each unopened blossom, 

 puncturing the blossom, according to Kollar (4), in the notched part 

 of the calyx, making an oblique opening, and immediately introduces 

 its egg into the deepest part. The egg is very minute, greenish- 

 white and transparent. It hatches in a few days (variously estimated 

 from a week to a fortnight), and then the young larva forces its way 

 into the embyro fruit and feeds on the developing kernel. 



When one fruit is damaged it eats its way into another. I found 

 that the larvre sent me from Eoss, some of which were nearly half 

 grown, attacked two plums before they were mature. 



The larva is creamy-white, in some cases having a faint pinkish 



tinge, the tail end is 

 somewhat attenuated 

 and the position usu- 

 ally slightly curved, 

 the head brown, the 

 six jointed - legs are 

 pale brown and there 

 are six pairs of pale 

 prolegs and an anal 

 pair. When full grown 

 the length is about ^ 

 inch when expanded. 

 The inside of the quite 

 small plums are com- 

 pletely hollowed out, 

 but in the larger fruitlets a space is merely shown around the kernel 

 which the larva has devoured. This cavity is sometimes filled with 

 moisture and decayed matter, but when the larvse are within, is 

 usually quite clean. No smell could be detected in any sent me, 

 such as is described by Ormerod (2), possibly the specimens she 

 received had lain together some time in the box, for it was noticed 

 that where this was allowed the fruitlets became a wet putrid mass 

 in a few days. 



On reaching maturity the larva? leave the fruit and enter the soil. 

 Those received in 1907 pupated from the 17th to the 26th of July, but 

 in 1905 some had entered the soil by the 5th of the same month. In 

 a few days I found they had spun small, roundish oval, brownish 

 cocoons, of the size shown in the photograph (Fig. 249), fairly close 

 to the surface ; they were spun up in the sand and very difficult to 

 detect owing to the sand sticking to them, but the parchment-like 

 cocoons \vere brownish in colour. The larvre remain in these cases 



[Horace Knight. 

 FIG. 250. THE PLUM FRUIT SAWFLY (Hoplocampa fulcieornw). 



