78 HOFMEISTER, ON 



By cell-multiplication extending on all sides, and dimi- 

 nishing downwards, the base of the rudimentary fruit be- 

 comes transformed into a turnip-shaped enlargement, sunk 

 into the tissue of the fruit-bearing shoot. This enlargement 

 is most vigorously and peculiarly developed (as is known 

 from Gottsche's beautiful observations, ' N. A. A. C. L.' 

 vol. xxi, p. 2) in the Geocalycese, where its upper margin 

 grows into the sheath surrounding the fruit-stalk ; and in 

 Calypogeia, where it grows into a highly delicate membrane. 

 A similar appearance is presented in Alicularia scalaris, 

 which, in the formation of its perianth, in some respects 

 resembles the Geocalycese : here four triangular fleshy lobes 

 which surround the base of the fruit-stalk, are developed out 

 of the enlargement of the lower end of the rudimentary fruit 

 (PL VII, fig. 10). These are less conspicuous in the true Jun- 

 germannige, and in Lophocolea. Fridlania dilatata exhibits 

 hardly any indication of them (PI. XII, fig. 9) ; lastly, in 

 Radula complanata there is only a very moderate enlarge- 

 ment of the lower end of the fruit-stalk, produced by a 

 transverse stretching and papillate expansion of the cells of 

 its outer surface (PI. XI, fig. 7). 



The development of the fruit of Fridlania dilatata (and 

 doubtless also that of the nearly-allied Lejeuniae) differs in 

 its middle stages not immaterially from that of the proper 

 Jungermanniae. In Fridlania the four apical cells of the 

 rudimentary fruit divide, even at an early period, by means 

 of longitudinal septa, which form an angle of 45 with the 

 side- walls, but diverge at a sharp angle from the longitu- 

 dinal axis of the fruit. The division of the apical cells 

 afterwards proceeds in the same manner as in Pellia and 

 Aneura. In the mean time the lower part of the rudi- 

 mentary fruit increases considerablv in thickness ; the cells 

 of its circumference divide repeatedly by longitudinal septa 

 parallel to the axis, alternating with radial septa. The 

 form of the rudimentary fruit is far less slender, its apex is 

 proportionately far wider, than in /. bicuspidata or Radula 

 complanata (PI. XII, fig. 8). The elaters and the spore- 

 mother-cells are produced by the multiplication of a hori- 

 zontal stratum of cells, which is separated by a double 

 layer above it from the cells of the apex of the rudimentary 



