176 Edmund B. Wilson 



FIG. 10 



26-chromosome forms 



tt-gj second division, polar, d from fern. No. 40, the others from fern. No. 42; a, (Photo 13) b, c, 

 show a single central hexad; in e and g the components are more loosely united; in d and /one supernumer- 

 ary is free. 



h-p, side-views, second division, from fern. No. 42 (Photos 22, 23) explanation in text. 

 q-u, growth-period, gran.. No. 60; q and r show the compound chromosome-nucleolus in oblique 

 and side-view, s, t, u, en face. 



