308 POMONA COLLEGE JOURNAL OF ENTOMOLOGY 



eggs deposited by an individual female, the facts being that under extremes, 

 such as lack of food for the adult, or excessive heat, the number of eggs 

 laid are greatly reduced, in such cases to one-half or even one-fourth nor- 

 mally laid. 



There is no marked egg-laying season, but the bulk of the eggs are laid 

 in the fall during the months of September, October, November, and December. 

 At this season the mealy bugs seem to be thickest and are more noticeable 

 than at any other season. The insect evidently prefers to pass the winter 

 in the egg stage, although large numbers of all stages appear during these 

 months. The idea of massing the eggs in great clusters for protection against 

 other insects, birds, and weather, seems to be carried out perfectly by ttie 

 mealy bug, for during these months much of the fruit, the limbs, and the 

 foliage may be entirely wrapped in cottony egg-masses. Large streamers 

 hang from the fruit in badly infested orchards, so that the eggs may be 

 gathered in handfuls. The position for depositing the eggs is determined 

 by the condition of the fruit upon the trees. There is no doubt but that the 

 mealy bug prefers the fruit to the foliage. The lemon tree, being a constant 

 bearer of fruit is subject to greater attacks than are orange trees from which 

 all of the fruit has been removed at some season of the year. The eggs are 

 deposited in the navels and at the blossom ends of the seedling fruit, as 

 long as there is any fruit upon the tree, in much larger numbers than upon 

 the limbs and leaves, but as soon as the fruit is removed the masses begin to 

 appear in great numbers upon the trunks and large limbs in the center of the 

 trees where there is more protection afforded. On a lemon tree a few of 

 the eggs are deposited upon the trunk and limbs of the tree, but the greatest 

 masses appear in the fruit clusters on the leaves near the fruit. Very few eggs 

 are to be seen during the months of ]\Iay, June, and July, and it is usually 

 at this season that the grower believes that the mealy bug has left. 



That the eggs are deposited in the ground for winter protection has never 

 been proved. I have searched very thoroughly to test this assertion and 

 have found but verv few eggs in the ground, and these were on the base 

 of the trunk at the surface of the ground. If the eggs are laid upon the roots 

 in the ground, the young upon hatching would naturally crawl up the tree 

 trunk to begin feeding, when the proper time came in the spring for them 

 to do so. To test this, we put tanglefoot bands around several acres of trees 

 and left them there for one winter and the early part of the summer. No 

 mealy bugs were caught worth mentioning on either side of the sticky band. 



The egg is the hardest stage in the life history of the pest to deal with. 

 In the fumigation work and in the spraying experiments, the large egg-masses 

 resisted tlie most. For testing the efficiency of hot water as an insecticide for 

 dipping mealy bug infected boxes, it was found that at 158° F. all of the insects 

 were killed, while it took 164° F. to kill all of the eggs. 



Eggs. Tn regard to the number of eggs laid by this insect, Mr. John J. 

 J")avis published in the F.iitnmological News, xix.. No. 8, p. 38,3 (1908), the 

 fnllowinir article : 



