302 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 



