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placed in the light, the continued growth of the rhizoids 

 soon became of a more protonema character, so that a 

 direct transformation of the main rhizoid axes to protonema 

 was called forth. Even in this case no branching resulted 

 and no buds were produced, neither in the light cultures nor 

 in the dark. 



The protonema originated from the basal portion of the 

 leaf and generali} 7 from some of the cells a little removed 

 from the end. There was no inherent tendency to the 

 production of protonema from a particular side of the leaf. 

 And, moreover, the growth occurred now from the contact 

 side, now from the free aide. In order to determine whether 

 the cells removed from the base had the power of producing 

 protonema, the leaves were cut transversely and kept in 

 condition favorable for growth for about two months. No 

 growth resulted from the apical portion, and from the basal 

 portion the growth was the same as in the whole leaf. 

 These experiments showed the power of growth to be localized 

 in the cells of the basal half of the leaf. It was also shown 

 that the production of protonema was only called forth by 

 the complete Separation of the leaf from the stem. 



The defoliated stems when kept in culture a short time 

 produced an abundance of rhizoids and protonema from the 

 region of the leaf axils, the protonema generally being the 

 more abundant. In the dark all of the growths from the 

 stem retained the nature of rhizoids, but when exposed to 

 light the further growth was of a decided protonema character. 

 The protonema production was not local but occurred in as 

 great abundance from one portion of the stem as another. 

 The defoliated stems generally produced one or two new 

 plants as lateral branches. The origin of these was not 

 definite, since they appeared now at the base, now the apex 

 and at intervening points. Whole plants placed under the 

 same condition as the defoliated ones also produced au abun- 

 dance of protonema direct from the leaf axil, the same as 

 in the defoliated stems. The production of new shoots was 

 also as abundant in the whole plants as in the case of the 



