HEPATICACE/E. 



[ 320 ] 



HEPATICACE^E. 



which represent the anthers of flowering 

 plants are called antheridia, those which re- 

 present the ovules, and produce the spore- 

 cases, are called archegonia or pistillidia. 

 The antheridia are small globular or oval 

 bodies, more or less stalked, which in the 

 Jungermanniese are composed of a double 

 layer of cells forming a membranous sac, 

 which, when ripe, bursts and discharges 

 numerous minute globular cellules, each of 

 which again bursts and discharges an ex- 

 tremely small filament, which moves about 

 actively in water (figs. 327 & 328). These 



Fig. 326. 



Fig. 327. 



Fig. 328. 



Haplomitrium Hookeri. 



Fig. 326. Axillary antheridia. Magn. 30 diams. 

 Fig. 327. Fragment of wall of antheridia ; the reniform 

 loose cells belong to the inner layer. Magu. 200 diams. 

 Fig. 328. Spermatozoids from ditto. Magn. 200 diams. 



organs mostly occur in the same situations 

 as the archegonia, and in some of the fron- 

 dose forms, such as Anthoceros, Eiccia, 

 Fimbriaria (fig. 322), &c., they are imbedded 



Fig. 329. Fig. 330. Fig. 331. 



Marchantia polymorpha. 



Archegonia in various stages. 



Magnified 100 diameters. 



in the substance of the frond ; in others, as 

 in Marchantia, they are immersed in the 

 upper part of special male stalked receptacles 

 (see MARCHANTIA) ; in the leafy forms, 

 they are free in the axils of the leaves (fig. 

 327). 



The archegonia or pistillidia are likewise 

 developed in various places, indicated here- 

 after in the tabular view of the families. 

 They consist of a kind of flask-shaped cellu- 

 lar case (figs. 329 to 331), enclosing at first a 

 single cell (embryonal cell), which subse- 

 quently grows into a sporange, apparently 

 after one or more of the spiral filaments of 

 the antherids have come in contact w r ith it, 

 by passing into the neck of the flask-shaped 

 sac (epigone). The embryonal cell becomes 

 increased by cell-division into a globular 

 cellular mass, which acquires various forms 

 in the different genera and families. The 

 epigone enlarges for a long time with the 

 growing capsule, completely enclosing it 

 (fig. 332), but after a time the latter bursts 



Fig. 332. 



Haplomitrium Hookeri. 



Young sporange enclosed in the epigone. 



Magnified 20 diameters. 



through the top of the epigone, which thus 

 forms a kind of sheath round the base of the 

 sporange or its stalk, and is called the vagi- 

 nule. The epigone may tear irregularly, so 

 as to form an irregular vaginule or calyx, or 

 regularly, so as to present a circle of teeth ; 

 or it may be slit horizontally in a circle, and 

 half of it carried up by the sporange, which 

 it thus surmounts as a hood or calyptra. 

 This epigone is sometimes surrounded by 

 another envelope called the perigone. This 

 originates at a later period and in a different 

 way, since it gradually springs up as a cir- 

 cular sheath around the base of the epigone, 

 and by continued growth comes to surround 

 it as a kind of cup, like the corolla of a 

 flower (fig. 324). In Marchantia, only one 

 archegone is found in each perigone; the 



