BLtYOPHYTES. 



43 



whose internodes were quite suppressed and which 

 never elongated, an unusual condition. 



Adventitious shoots are very common in Bryophytes. 



Necker was the first to induce these shoots by cutting 

 up portions of the th alius of Marchantia and Fegatella. 



Forest Healcl found that buds arose directly from 

 detached portions of the stern of the moss Fissidens, 

 i. e. without the intervention of a protonema. 



Goebel found on a detached piece of the th alius of 

 the liverwort Blyttia Lijellii that buds arose on the 

 apical portion of the midrib ; on a piece of the thallus- 

 wing, i. e. devoid of midrib, they were irregularly 

 distributed on the surface (PL IV, fig. 2). He made 

 numerous other investigations with the liverworts 

 Riella and Sphserocarpus. He also describes how in 

 the weak " Ulvula" forms of the thallus of Metzijeria 

 f areata, whose cells were largely dead, and in which 

 normal growth was suspended, there developed narrow 

 adventitious shoots, without a midrib or rhizoids, 

 which may be even filamentous, representing a kind 

 of reversion to the juvenile form. 



Schostakowitsch describes experiments with various 

 liverworts in connection with the regenerative proper- 

 ties possessed by them. In Freissia, commutata he 

 found that adventitious shoots arose from the surface 

 of the proembryo when placed in semi-darkness. In 

 several others, e..g. Anthoceros, Riccia, and Lophocolea, 

 he found that shoots arose on the lower side at the 

 edge of cut pieces of thallus ; in some cases rhizoids 

 were first formed, and afterwards, from the same 

 region, young plants sprouted. 



Vochting made numerous regeneration-experiments 

 with liverworts of the March antiaceae-group. He cut 

 off pieces of thallus and placed them on moist sand. 

 As a result fresh thallus-shoots sprouted from the lower 

 side of the midrib at the apical end of the piece, and 

 remained attached to the piece from which they grew. 

 On older pieces, two or three shoots arose. Small bits 



