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the leaf is still in connection with the stem, the plastic 

 material can be transported to other younger and growing 

 parts; in the detached leaf on the other hand the escape 

 is cut off, and thus raay favor the production of rhizoids 

 and buds. The simple cutting of the leaf in itself seems to 

 be however the important factor, that is, the complete 

 Separation of the leaf from the stem affords the Stimulus 

 for growth, which is then applied to the production of 

 rhizoids and new leafy shoots. 



When the stems of Mnium are stripped of leaves and 

 kept in conditions favorable for growth, they will produce 

 new shoots which originate as axillary branches. As is often 

 noticed in nature, the stems produce an abundance of rhizoids 

 and these in greater abundance from the region of the stem 

 which has given rise to a shoot. In no case however was 

 a production of protonema direct from the stem to be 

 observed, and the rhizoids grew for months without giving 

 rise to any protonema branches. The production of new 

 shoots from the stems occurred as well in the dark as in 

 the light; in the dark however the new shoots produced 

 smaller leaves, and were more slender and elongated. The 

 shoots used for experimentation were laid horizontal, and 

 the lateral shoots grew erect, both in the dark and in the 

 light, thus showing a well marked negative geotropism. 

 The production of the new shoots was not called forth by 

 the defoliation , but only accelerated thereby , since whole 

 plants subjected to the same conditions produced new shoots 

 as lateral branches, according to the manner of branching 

 in nature. The stems also showed quite a distinct tendency 

 to the production of shoots from the region of the morpho- 

 logical apex. Defoliated stems were grown in a vertical 

 Position in a moist Chamber, part with the morphological 

 apex uppermost, part with it directed downwards. The 

 result was that in the majority of cases the new shoot 

 appeared a short distance below the apical end. In some 

 cases the stems gave rise to to several shoots, and some of 

 these were often well removed towards the basal end. The 



