CHROMOSOMES OF THE REDUVIIDAE 345 



for the study of the continuity of the ova from the tip of the end 

 chamber to maturity. Figure 9, A and B are two drawings of the end 

 chambers from a 3^oung ovary. It will be seen that both show two 

 zones distinctly, the apex of small nuclei corresponding to zone 

 A and the rest of the end chamber composed principally of large 

 nuclei corresponding to zone B of Protenor. There is no dis- 

 tinct region, however, which can be called zone C. A few small 

 nuclei (fig. 9, A and B) are found near the lower end of the region 

 which corresponds to zone B and it is possible that these nuclei 

 are the representatives of zone C, although they are not confined 

 to a definite region as in Protenor. As to the origin of these small 

 nuclei in Gelastocoris, I am not quite certain. I am willing to 

 grant that they may arise by migration, unchanged, from the apex 

 or that they may arise by fragmentation of the large nuclei. In 

 this case it is of little concern where they arise, as the evidence in 

 Gelastocoris proves conclusively, I think, that the ova do not arise 

 from these small nuclei. Figm*es 9, A and B, and 10 show a 

 number of nuclei in the synaptic stage (S) . That these nuclei in 

 this stage are the true oocytes is demonstrated in figures 7, F and 

 8, ^ . Figure 8, A shows a young oocyte at the base of the terminal 

 chamber and as it starts down the tube (similar in position to the 

 oocyte ov in fig. 10). The cytoplasm is just beginning to form 

 around the nucleus and the chromatin is in practically the same 

 condition as in figure 7, F, where the double threads are coming out 

 of the contraction phase. This clearly demonstrates that the 

 oocyte starts down the tube shortly after the synaptic stage. 

 Hence my conclusion that all the nuclei in the synaptic stage are 

 young oocytes. As is shown in figure 9, B, these nuclei in the syn- 

 aptic stage (S) are scattered among the large nourishing nucfei, 

 extending up as far as the border line between the large nuclei 

 and the small nuclei of the apex. This figure along with figure 7 

 shows that these nuclei undoubtedly arise by the growth of the 

 small oogonial nuclei at the apex and hence in this form there is 

 no break in the continuity of the cells from the oogonial stage to 

 the fully developed ova. 



While the evidence in Gelastocoris warrants the above con- 

 clusion, I by no means wish to generalize and say that this must 



