86 CHARLES V. M( iRK ILL. 



large chromosomes all more or less constricted and a small nodule 

 close to the central one, which probably is the w-chromosome. 

 Fig. 2, b, shows another in somewhat oblique view with MAID 

 large dyads, and the w-chromosome dyad, the latter faintly 

 stained. Fig. I, /, and PI. I., ti, show side views of two more 

 polar body groups; in Fig. i,/, the w-chromosome dyad is dis- 



**' 



t t * 



a 



b 



A* ' 



f 



"'' 







FIG. 2. Archimerus allcrnatus. Second oocyte- (polar) division, a. inctaphase- 

 Rroup, oblique view, b, chromosome-group of the first polar body from the s;uiu- 

 egg as the last, c, metapbase-group, polar view, d and c, metaphase groups, >idi- 

 view. / and g, daughter groups from the same anaphase-spindlc, oblique vi<-\\. 

 h and i, anaphase. oblique view, in two sections. 



tinctly seen. All the chromosomes show the typical con^i i id ion 

 as though ready for a second division. Il<>\\r\rr no spindK- i- 

 formed and no division takes place except that in indixidual c hro- 

 mosomes the halves of a dyad may separate of their own accord, 



