THE HIGHER CRYPTOGAMIA . 53 



early as the eighth day after the spores have been scattered 

 over the moist, slimy mass, the expanding inner membrane 

 ruptures the outer membrane, and protrudes in a vesicular 

 form through the fissure (PL IX, fig. 2). It contains numer- 

 ous very beautiful, small, emerald-green chlorophyll bodies. 

 The protruding portion of the inner membrane is soon 

 divided from the remainder of it by a transverse septum. 

 By continual division of the fore-cell (that one, namely, 

 which is furthest from the remnants of the exosporium) by 

 means of transverse septa, which septa are always preceded 

 (as in higher plants) by the appearance of two new nuclei in 

 the mother-cell (PI. IX, figs. 3 7) the germinating spore 

 is converted, within a month after it has been sown, into a 

 simple row of cells, seven or eight in number. 



In the apical cell, and often also in the interstitial cells, 

 with the exception of the one or two lowest, division by 

 longitudinal septa now commences contemporaneously with 

 an active longitudinal growth of the germ-plant, which latter 

 growth results from the division of the apical cell by means of 

 alternately inclined septa. In this way there originates a 

 small band, formed of a single layer of cells, lying side by 

 side in pairs (PI. IX, fig. 8), near the lower end of which 

 a slight thickening of the cellular tissue is often found, 

 originating from the division by more than one longitu- 

 dinal septum, of some of the interstitial cells of the cellular 

 thread produced by the germinating spore. The ribbon- 

 shape of the fore end of the germ -plant is soon changed to 

 that of a cylinder through the division by radial longitu- 

 dinal septa of the cells of the second order, produced by 

 the division of the terminal cell by inclined septa (PI. IX, 

 figs. 10 4, 11 M,C ). Prom some of these cells short cellular 

 branches sprout out always close under the septum dividing 

 the particular cell from the next higher one. These 

 branches are soon separated from the inner cavity of their 

 mother-cell by a transverse septum. They are arranged in 

 two vertical rows, the lower being placed (with respect to 

 their attitude) irregularly upon the germ- plant, the upper 

 ones being very regularly alternate (PI. IX, fig. 9). The 

 lower ones do not undergo any change, but in the third or 

 fifth, reckoned from below, division occurs by a transverse 



