134 THE MOSS-ANIMALS, 
arise from the thickened rim, and draw out between them 
a web, which afterwards receding externally, becomes 
the veil, and the wall of the tube is merely an elongation 
of the membrane connecting the rim of the sac with the 
parent. 
The cell-bulb does not protrude externally until these 
organs are mapped out. The young one, though sti 
very imperfect, begins to stretch forth its arms as soon as 
the cell, or cænæcium, as it is more appropriately called, 
is well extended, and long before the characteristics reach 
perfection, gives other evidences of its natural precocious- 
ness in the statoblasts and regular buds, which spring up 
in their respective places within the ccencecium. At in- 
tervals two buds will sprout in different directions, orig- 
inating new branches, and thus a dendritic colony is 
gradually built up, which owes its origin entirely to one 
animal. Consequently the outer branches are the young- 
est, and often, as in plants, these are vigorous and quick 
with life, while the parent trunk is but an empty case, — 
frequently with nothing left to indicate its position but — 
the decaying cænæcia, or their faint tracery in the slime. 
The second mode of reproduction, by egos, takes place | 
only in the newly established colonies during the earlier 
summer months. These eggs are little colorless vesicles, 
developed internally from a bead-like swelling on the free 
side of the wall, near the orifice. When ripe they are 
dropped into the cavity of the cænæœcium, and there meet 
- with the fertilizing filaments which have been developed 
i1] 
neither male or female, but of the collective gender, an 
ermaph BS o n| inir g the r A a 
