298 



MANUAL OF BOTANY 



basal portion or venter containing the oosphere, and surmounted 

 by a neck or narrow portion, the length of which varies in 

 different groups of plants {fig. 497). 



A good deal of difference in completeness of differentiation 

 of the ganietangium is fomid in different groups. Its reduction 

 reaches its greatest extent in the Angiosperms, where the 

 archegonium is apparently unrepresented, or represented only 



Fig. 491. 



Fig. 490. A. Portion of the axis of Ghara 

 fragilis. s. Nucule or oogoniiiiQ. a. Globule 

 or antlieridium. b. luteruode. c. Crown or 

 corona of nucule. j3. Abortive leaves. /3', 

 j3", )3". Sterile leaflets, b. sk. Nucule, and a, 

 globule, both in an early stage of develop- 

 ment, -w. Nodal cell of leaf. u. Union cell 

 between it and basal node of globule. /. 

 Cavity of internode of leaf. hr. Cells of leaf 



covered with cortex. After Sachs. l''i>/. 



491. A portion of a filament, fli, oifig. 492, 

 in the cells of which the antherozoids are 

 developed ; vnth. a 2-ciliated antherozoul by 



its side. Fig. 492. A globule cut in half 



to show the oblong cells or manubria, c, and 

 the septate fi'aments, J\l. After Henfrej'. 



Fig. 492. 



:^4^^^ 



by the oosphere, the latter being one of the few cells to which 

 the gametophyte is reduced, all of which lie in the inside of the 

 megaspore. In such Fungi as possess an oogonium {fig. 489, og) 

 it is much reduced, and consists only of a swollen head at the 

 end of a special branch, from which both oogonium and pollino- 

 dium arise. 



In the Bed Seaweeds the female organ, as we have seen. 



