96 HOFMETSTER, ON 



large basal cell of the central string. The upper of the 

 two newly formed cells is then divided by a septum in- 

 clined in the opposite direction (PI. XIII, fig. \G b ). In 

 the apical cell of the now 3 -cellular young fruit the 

 division is repeated several times by alternately inclined 

 septa. The cells of the second degree divide by radial 

 longitudinal septa, and the cells thus produced divide into 

 three-sided inner and four-sided outer cells, after the manner 

 of the one row of cells of the third degree belonging to 

 the archegonium. In the four- sided cells, the division is 

 repeated by radial septa, and then by longitudinal septa 

 parallel to the axis of the fruit (PL XIII, figs. 17, 18). 

 When the young fruit, which from first to last is almost 

 globular, has attained its full size, the somewhat tabular 

 cells of its upper surface divide by a longitudinal and 

 transverse septum perpendicular to the outer surface, so that 

 the outermost cellular layer of the fruit consists of cells of 

 which the basal outline is four times smaller than that of 

 the inner cells (PI. XIII, fig. 19). 



In each of the latter there ensues a well-defined, gelati- 

 nous thickening of the cell-wall (PL XIII, fig. 19). Soon 

 afterwards the cells become disconnected by the dissolution 

 of the oldest outermost portion of the cell-wall. The 

 spherical cells thus set free are the mother-cells of the 

 spores. In each of them four special-mother-cells origi- 

 nate, each of which produces a spore. After the indivi- 

 dualization of the spores the wall of the half-ripe capsule 

 is absorbed, so that the ripe spores lie free in the cavity of 

 the globular calyptra. This latter is formed by the re- 

 peated division into two parts of the cells of the ventral 

 portion of the archegonium, by means of septa perpendi- 

 cular to the outer surface, such division alternating once 

 with a division by septa parallel to the outer surface. 

 The calyptra of the half-ripe fruit consists of two layers of 

 cells (PI. XIII, figs. 17, 19) ; towards the period of maturity 

 the inner one of these disappears. The neck of the arche- 

 gonium lasts till the fruit is ripe. The cells often assume 

 a beautiful wine-red colour. In rare instances those cells 

 of the impregnated archegonium which lie beneath the 

 central cell of the ventral portion multiply, so that the 



