16 The Ohio Naturalist. [Vol. XIII, No. 1, 



where the break occurs become fastened together, making some- 

 what irregularly shaped rings, some of these rings having little 

 loops in them (Figs. 18b, 19). 



In other cases, after the break occurred, the ends of the loops 

 did not fuse, but projected as free limbs (Fig. 19). There was a 

 great deal of difference in the newly formed chromosomes. In 

 the figures, all the chromosomes are shown in one plane as pro- 

 jections, but under the microscope they were more easily disting- 

 uished and the details could be more easily traced out by focusing. 

 The large chromosomes in the middle of Figure 18 which overlap 

 are figured separately to show their actual form; 18a being the 

 one on top and 18b the one below (Figs. 18a, 18b). Figures 17, 

 19, 18, 20, and 21, show the chromosome differences plainly; six 

 are quite large, six small and two of intermediate size. The dif- 

 ference in shape is well shown in Figures 19 and 20. In the 

 earlier stages it can easily be seen that some of the chromosomes 

 have not doubled up nor formed com]3lete rings. Gradually all 

 of them twist up tighter until most of the chromosomes appear 

 as small irregular masses (Figs. 21, 22). The nuclear wall has 

 practically disappeared by the time the chromosomes have fully 

 contracted (Figs. 21, 22, 23). By this time, also, the sporocyte 

 has rounded up and withdrawn from the neighboring cells. The 

 cytoplasm appears spongy and, in most cases, is withdrawn from 

 the cell wall. The nucleolus seems to disappear at about the 

 time the nuclear membrane becomes indistinct. What becomes 

 of it was not determined but in some cases nucleolus-like masses 

 were seen in the cytoplasm. As will appear from the above 

 description and consideration of the figures presented, it becomes 

 evident that the details of chromosome formation in Fuchsia 

 does not agree with that of Oenothera as described by Gates, 

 Davis and Geertz. The loops are fonned from a very slender 

 spirem and no thickening into a chain of univalent chromosomes 

 is apparent. The incipient loops before the separation occurs 

 are quite distinct and these loops were followed through their 

 development and gradual transformation until the fully fonned 

 bivalent chromosomes were present. Although the behavior of 

 the spirem is somewhat different from that reported for Oenothera 

 the final result is identical. The spirem breaks up apparently 

 into chromosome pairs which, coming to lie side by side, by 

 folding and twisting together are transformed into bivalents in 

 the same manner as described by Gates. The bivalents are 

 formed by an end to end fusion and subsequent folding of pairs 

 of univalents. The number of chromosomes could be counted in 

 ten or twelve preparations and each count was fourteen. Figures 

 22 and 23 show the fully formed chromosomes before the fonna- 

 tion of the spindle. In Figure 22 one of the large chromosomes 

 lies out separate from the rest and all except this large one are 



