14 



BULLETIN 643, U. S. DEPARTMENT OF AGRICULTURE. 



of the ovaries of watermelon bloom that in dr}^ weather the remains 

 of the bloom wither and become mummified, as shown in figure 15. 



An examination of the buds of the male bloom in any field through- 

 out the coastal regions of the Island of Oahu, particularly during 

 the months from March to November, will reveal the severity of 

 attack centered on this portion of the plant. 

 Wherever the buds have been attacked, a whit- 

 ish gumlike excretion exudes which hardens 

 about the point of attack. On cutting the buds 

 lengthwise, batches of eggs can be seen among 

 the folds of the corolla, or in the stamens and 

 receptacle, as shown in figure 11 (p. 12). As 

 the eggs are pure white and are in clusters 

 of 2 to 10 or more, they are seen easily with- 

 out the aid of a lens. If the eggs have been 

 laid from 2 to 6 days, the inside of the bud 

 may have been already eaten out by the rap- 

 idly developing larvae. Buds attacked before 

 they are half grown usually are destroyed com- 

 pletely before the blossom unfolds. Figure 11 

 shows three stages in the destruction of the 

 staminate bloom. The bud a is a mass of 

 decay within ; the stamens have been devoured 

 and the larvae already have begun to burrow 

 about the base: l> shows a bud that has been 

 severed by the feeding of the larvae and nas 

 fallen over under its own weight; and c is the 

 upright stem of the bud, after the essential 

 parts of the bloom have been ruined and have 

 fallen to the ground. Although attack may 

 occur so late in the development of the male 

 bloom that the corolla can unfold, it is more 

 often than not that eggs, or even } 7 oung larvae, 

 can be seen on the inside of the corolla when 

 the flower is in full bloom. The melon fly never 

 attacks the bloom after the corolla has unfolded. 



Fig. 13. — Pis tillate 

 bloom of squash in 

 which larvae of the 

 melon fly have so de- 

 voured the unferti- 

 lized ovary that the 

 bloom is destroyed be- 

 fore the flower can 

 unfold. (Authors' 

 illustration.) 



INJURY TO NEWLY SET FRUITS. 



The greatest destruction among fruits usu- 

 ally occurs when they are very young, either 

 before they are fertilized or just after they have set. At this 

 stage of development the young fruits are expanding very rap- 

 idly. Figure 16 shows the damage done to three young pumpkin 

 fruits. About the damaged areas calluses are formed by the fruit 

 in an attempt to repair the damage, but this attempt seldom 



