180 THE WORLD OF THE SEA. 
distinct individuals. These remain adherent to their mother, and 
this is the first settlement of a new colony. 
The arrangement of the members of each association is very 
varied. But throughout this great diversity a rigorous and 
geometrical regularity is preserved. The inhabitants of these 
colonies are sometimes very numerous, though generally this is 
not the case. They are joined together indissolubly for weal or 
for woe; the same sunbeam cheers the whole; they curtsey to 
the same wave, and all tremble under the blast of the tempest. 
Each member of the colony fills its particular station, and performs 
its assigned duties with exactitude and zeal. No inharmonious 
jangling is heard, no factions strive for the rule ; no divisions injure 
THE GILDED BOTRYLLA. 
(Botryllus gemmienus.) 
their prosperity, or threaten their peace. The ascidia furnishes us 
with the beau-ideal of a republic, where the citizens are intimately 
joined to each other, and where there is but one spirit for the 
common weal. 
The Botryla is another interesting association of mollusk life. 
Their colonies have seldom more than twenty members. They 
are somewhat flat, and adhere by their sides to some submarine 
body. They are so arranged as to form a kind of wheel. If 
we touch one of the branches, that particular mollusk contracts 
itself; when, however, we touch the centre, they all contract. 
The buccal orifice of each mollusk is placed at the outer extremity 
of the radius, but the intestinal openings abut on the common 
cavity which forms the centre of the wheel. Here is another 
