90 FISHES I HAVE KNOWN 



the physalia, or Portuguese men-of-war. This 

 medusa, which grows to a large size, must not be 

 confounded with a nautilus. The latter has a shell, 

 while the medusa has a tough, membranous, bladder- 

 like body with a kind of serrated dorsal fin, a! short 

 curved tail, and, streaming below the bladder, a 

 thickish central tentacle, surrounded by many very 

 fine antenna;. It looks something like a brilliantly 

 coloured cocked hat, or a glengarry cap, floating 

 aimlessly on the water ; but it has powers of 

 locomotion, by means of tentacles, and a blue- and 

 purple sail-like membrane (erectile at will) at the 

 back fringed with rose-pink, that catches the wind 

 and helps it along. 



At times the ship passes by an immense number 

 of these men-of-war of all sizes. They can sting 

 like gigantic nettles, and if brought on board, 

 inexperienced passengers are entreated by the 

 more knowing ones not to meddle with them. 



Once, when our ship's carpenter was bathing in 

 a sail secured to the side (a precaution against 

 sharks), he was so severely stung by one of these 

 " Portugees," that he became paralysed, and after- 

 wards developed a disease like the itch, probably 

 caused by the acrid matter in the beast's tentacles, 

 and not, as some of us suggested, by an\' electric 

 property in them. 



