"362 THE OCEAN. 
shell, resembling a collection of air-bubbles, but 
composed of a delicate white membrane, inflated, 
and puckered on the surface into the bubble-like 
divisions alluded to; it is oblong, about an inch in 
length. The buoyancy of this float supports the 
animal at the surface, where it lies with the con- 
vexity of the shell downward. Three or four drops 
of a blue liquid are contained in the body, which 
has been supposed to answer the purpose of con- 
cealment in time of danger, by imparting an obscu- 
rity to the water; but it is hardly sufficient for this 
purpose, as the whole quantity secreted by one 
animal will not discolour half a pint of water. Be- 
neath the float, at certain seasons, the eggs are sus- 
pended by pearly threads; and as the floats are fre- 
quently found in great numbers with eggs thus 
attached, but separate from the original animals, 
it is thought that they have the power of throwing 
off this appendage and forming a new one; in which 
case it serves the purpose of sustaining the eggs, and 
probably the young, within .the reach of. the light 
and heat of the sun. 
The Portuguese Man-of-war (Physalis pelagica), 
numerous in the warm parts of the Atlantic, is still 
more abundant in the seas of which I am writing. 
It is a beautiful little creature, though of very 
simple structure, consisting merely of a semi-trans- 
parent membranous bag, round at one end, and 
pointed at the other, along one side of which runs a 
wide membrane, puckered into perpendicular folds, 
and capable of being contracted and dilated; while 
from the opposite side depends a thick fringe of blue 
