Page:The Olive Its Culture in Theory and Practice.djvu/145

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THE OLIVE
119

length as the abdomen, and is a dark red. The point of the borer is black. The male differs from the female by the absence of the borer, and by having the posterior margin of the third abdominal ring fringed with black hair turned backwards. The body is one-sixth of an inch in length.

The date of the most copious hatching of these insects is variable. When the olive has reached its greatest development (about the end of July) the flies just transformed from the pupa appear. Copulation then takes place, and the female, choosing the ripest fruit, deposits her eggs there, usually one egg to each berry. (Fig. 1 a. c. b.b).

In less than twenty four hours an amber spot will appear on the surface of the olive where the egg was deposited, which will turn darker after a little time. The spots can be seen only when the berry is green, as it grows ripe they are hardly discernible. Each female deposits about one hundred eggs. In ten or fifteen days these eggs hatch. The larva, with the hooks of borer, attacks the pulp of the fruit, and then makes its way into the seed, boring a winding tunnel. The pulp of the berry above the tunnel will become reddish wrinkled and transparent, thus showing the presence of the enemy. The larva lives from thirty to forty days. Some change into the pupa form inside of the seed and also into flies, but the greatest number abandon the berry by making an aperture through the pericarp and change into pupae either in the ground, or in the crevices on the trunk of the tree.

The flies appear after thirty or forty days. The duration of the three periods, that is the egg, larva and fly may vary as much as twenty days from the foregoing, as eggs deposited at one time may be hatching for twenty days consecutively, and eggs, larvae, pupae, and flies can be found at the same time.

The pupae of the last generation do not change in the given time, that is in thirty or forty days but remain in that state through the spring till the fruit has reached some size and the prosperity of their