46 



one, and the other had the one large nucleus and two small ones. 

 One egg four hours old showed but the one large nucleus. Of five 

 eggs from one to four hours old, one had two nuclei, the large one 

 and one small one; each of the other four had only the large nucleus. 

 One egg, from one to twelve hours old, had but the one large nucleus. 

 In an egg killed eight hours after laying, I found three nuclei, 

 each about one third as large as the large ones mentioned above, and 

 two smaller ones, all having the same characteristic vacuolated ap- 

 pearance. All five were in the peripheral layer of protoplasm near 

 the posterior end of the egg. In another egg eight hours old there 

 was but the one large nucleus at the posterior end of the egg; but 

 in addition to this, in the midst of the yolk at about one-third the 

 distance from the anterior end, appeared a few small irregular stel- 

 late nucleated masses of protoplasm, having exactly the same ap- 

 pearance as the ones that appear successively more numerous in some- 

 what later stages. In an egg eleven hours old, there was but the one 

 large nucleus at the posterior end, and near the anterior end there 

 were a few small irregular nucleated masses of protoplasm. In addi- 

 tion to these, scattered throughout the yolk in the posterior half of 

 the egg, were a number of small stellate masses of protoplasm, most 

 of which had exactly the same appearance as those at the anterior 

 end except for the fact that I could not see that they were nucleated. 

 Some of them looked very much as though they were detached frag- 

 ments of the large nucleus, having the same vacuolated appearance. 

 The yolk is now changing its appearance, becoming liquefied, the 

 yolk granules breaking down and the vacuoles increasing in size and 

 number. In a thirteen-hour stage I found only the one large nucleus. 

 In an egg twenty hours old I found one nucleus, very large and very 

 irregular (Figure 4), at the posterior end in the usual position of 

 the large nucleus. In addition to this, in the yolk occur a number of 

 small, rather deeply staining, vacuolated masses, that have the same 

 appearance structurally as the large nucleus. They appear either to 

 be made up entirely of cytoplasm or entirely of karyoplasm, that is, 

 there is no part more deeply staining than the rest to indicate that 

 they are nucleated masses of protoplasm. The large nucleus was 

 .09 mm. across, and the largest of the small masses was .025 mm. in 

 diameter. In the anterior half there are scattered throughout the 

 yolk near the center of the egg, a number (about twenty altogether) 

 of stellate masses of protoplasm with small, globular, deeply-staining 

 nuclei. These generally occur in pairs, indicating their origin by 

 division. The conditions which are described above must be similar to 

 those found by Weismann in Cynipidcc. "According to Weismann, 



