24 
Choice Ferns tor Amateurs. 
(Fig. 18), slender, but coiled spirally in two or tliree 
turns, and provided with a tuft of fine hairs, or 
cilia, at one end. These antherozoids somewhat 
resemble microscopic tadpoles, and more actively in 
the moisture surrounding them. Their function is 
to fecundate. This object is effected by means of a 
more or less rapid motion, to which the body is 
Fig. 19. Young antheridium Fig. 20. Ripe antheridium 
Fig. 21. Immature archegonium, showing c, canal, still closed 
above, and filled by the canal=cell ; e, e, epidermis ; n, 
neck=cells ; o, oosphere (much magnified). 
subjected by the action of a number of delicate and 
irritable hairs, situated at one of the extremities of 
a flattened helicoid-like thread, that always accom- 
panies this club-shaped vesicle. In most prothalli, 
however, a process of cell-division goes on in the 
young antheridium, whereby it is finally made up of 
a layer of cells surrounding a central cell (Fig. 19), 
and in this the parent cells are developed, and 
produce antherozoids. The outer coat, formed by 
0 
showing : c, central cell, 
filled with parent cells 
of antherozoids ; e, e, 
epidermis of prothallus 
(much magnified). 
from which antherozoids 
have been shed by opening 
at o.— c, empty cell ; e, e, 
epidermis (much magni= 
fied). 
