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sively from the cells of the base which occupied the position 

 next the costa. 



The defoliated stems gave rise to new branches as axillary 

 shoots, both from the main axes and from the side branches. 

 These appeared without any apparent regularity with reference 

 to base or apex of the stems, and also as well in the dark 

 as in the light. In the dark the growth was more rapid, 

 producing longer and slenderer shoots with very reduced 

 leaves. Although the stems were cultivated for about two 

 months no protonema production direct from the stems was 

 observed. The prodnction of rhizoids was not general only 

 here and there a few being produced. The whole plants 

 brought in the same conditions as the defoliated stems,. 

 produced new plants in apparently as great abundance. 

 The rhizoid production was about the same, so it was im- 

 possible to say that either rhizoid or shoot production was 

 accelerated by defoliation. 



LEPTOBEYÜM PYRIFORME. 



The leaves of Leptobryum compare very favorably with 

 B. rutabulum in the extent to which they produce proto- 

 uema, perhaps not more than one in ten of the leaves used 

 showing the formation of a new growth. The first appearance 

 of protonema was noted after the leaves had been in culture 

 for nearly three weeks. The same as in Bryam and Brachy- 

 thecium, the first growth was semi-protonema in character. 

 With continued exposure to light and increase in length,. 

 it assumed more and more the protonema character. 

 Towards the distal end the cells were much shorter, abund- 

 antly filled with Chlorophyll, and with perpendicular cross- 

 walls. Even in the light the branching remained suppressed 

 and only long, unbranched filaments of abont 1 cm length 

 were produced. In the cultures in the dark the filaments 

 remained distinctly rhizoid in nature and reached the length 

 of about 1 cm after four weeks of growth. When leaves 

 which had remained in the dark for about four weeks were 



