314 D. H. TENNENT. 



The individual from which I obtained the eggs I identified as 

 Asterias forbesii although it will be noted that the number of 

 chromosomes agrees with the germ-cell number in my sperma- 

 togenesis material of Asterias vulgaris. 



In these eggs, as in the other C0 2 eggs described, the form of 

 the chromosomes is irregular but owing to the smaller number 

 may be counted readily. The equatorial plate, the daughter 

 plates, etc., all show the same number, — i. e., nine (Figs. 11 

 and 12). 



Fig. 13 shows the extremely irregular form assumed by the 

 chromatic material in anaphase and explains the reasons for the 

 complexity exhibited by sections such as those from which Fig. 

 10 was drawn. 



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13 14 



Fig. 13. First segmentation C0 2 egg. Anaphase. 



Fig. 14. First segmentation C() 2 egg. Late anaphase. One chromosomal 

 vesicle. 



As shown in Fig. 1 3 this chromatic material at this stage is in 

 the form of greatly twisted threads. A single section may cut 

 the thread in several places. 



In later anaphase these threads are drawn out, passing through 

 a variety of changes and at last are embodied in chromosomal 

 vesicles which unite to form the daughter nucleus (Fig. 14). 



Clearly then, this egg with its oocyte number of 9 chromo- 

 somes does not exhibit the phenomenon of " autoregulation." 



