280 



BOTANY. 



place late in the season, is as follows : where two filaments 

 cross each other or come into close contact they swell 

 slightly and send out from each a short branch ; one of these 

 thickens and assumes an oval form, becoming at the same 

 time separated from the filament by a partition ; this is the 

 carpogonium (///, c, Fig. 188, and c, Fig. 189). From the 

 swollen part of the other filament a corresponding branch is 

 given off, which grows up in contact with the carpogonium ; 

 near its extremity it forms a partition, which thus cuts 



E p 



Fig. 188. /., conidia-bearing hypha of Sphcerotheca pannofa. 77, the ripe f=poro- 

 carp of the same ; a, the single ascus escaping from the perithecium. h; only a few 

 of the hypha-like appendages of the perithecium are shown. 77/.. sexual organs of the 

 same; e, carpogonium : p, antheridium. IV., the formation of the perithecium by 

 the growth of the enveloping cells, h ; c, carpogonium ; p, antheridium. V., section 

 of the young sporocarp of" Sphmrotheca Castagnei ; c, carpogonium : a, the young 

 ascus ; A, A, cells of the perithecium. /. and II. after Tulasne ; 777.- V. after De 

 Bary. 



off a small rounded terminal cell, the antheridium (///., p, 

 Fig. 188, and b, Fig. 189). Immediately after the forma- 

 tion of the antheridium the effect of fertilization shows itself 

 in the growth from below the base of the carpogonium of eight 

 or ten branches, which join themselves to its sides and to one 

 another, finally completely investing it (IV., Fig. 188, and^, 

 Fig. 189). Each of these joined enveloping branches be- 

 comes transversely divided several times, thus giving to the 

 covering layer a distinctly cellular structure. The enclosed 



