Some Degenerative Phenomena in Drosophila Ovaries

There are several reasons why it is of interest to examine the ultra-structure of degenerating cells. In the first place, processes of cellular degeneration may be involved in normal developmental processes. In the formation of the insect egg, for instance, a great deal of the ooplasm is derived from the substance of the nurse cells, which degenerate and eventually disappear as the oocyte reaches its final stage of growth. Again, the follicle cells, after secreting the chorion, degenerate and eventually disappear. As will be demonstrated in this paper, degenerating cytoplasm often exhibits some rather well-organized and elaborate structures which might have been taken, if one did not know of the cells in which they were found, to be organelles concerned with synthetic activities. A study of such materials suggests the dangers of too easy interpretation of some of the appearances seen in healthy cells.