2 HOFMEISTER, ON 



two indentations exhibited by the fore edge of each 

 shoot (which indentations arise from the amalgamation 

 of three growing masses of cells, viz., a median shoot 

 and two side shoots) three cellular protuberances origi- 

 nate, first a median one, and then two side ones. They 

 grow into one another nearly up to their fore edge, and 

 unite on either side with the median lobe of the fore 

 edge of the next older shoot. By further elongation 

 they become new shoots, producing an increase in the 

 breadth of the median lobe. The ramification of the 

 plant is therefore irregularly dichotomous, depending 

 upon the continual formation of side shoots on either 

 side of a median shoot, which latter is limited in its 

 longitudinal growth — a mode of ramification which, in 

 the case of phasnogamous plants, has been called by 

 Schimper " Dichassium." As the new shoots, lying in 

 one plane, diverge from one another at angles exceeding 

 90°, a succession of three generations of shoots suffices 

 to render the outline of the entire plant circular. The 

 habit of the plant depends, for the most part, upon the 

 extent to which the three component parts of each new 

 shoot amalgamate longitudinally inter se and with the 

 median lobe of the fore edge of the next older shoot. 

 Where the elongation of the lower part of the new shoots 

 begins at a late period, there the extent of the amalga- 

 mated growth is very considerable. This is the case 

 with specimens of Anthoceros Icevis growing in sunny 

 open fields. Here, in consequence of the perishing of 

 the oldest shoots, those namely which originate directly 

 from the spore, the plant usually has the appearance of 

 an exactly circular or slightly lobed expansion of dark 

 green, succulent cellular tissue. The extent of amalga- 

 mation of the shoots is much smaller in Anthoceros 

 punctatus, and still less in plants of Anthoceros Icevis 

 which have grown in moist shady places or in higher 

 temperature (as, for instance, in pots which have been 

 long under glass). The ramification of Anthoceros is 

 similar to that of the Kicciese, the Marchantieae, and 

 several leafless Jungermannise, as, for instance, Pellia. 

 In Anthoceros, however, the resularitv of the ramification 



