THE PORTUGUESE MAN-OF-WAR. - 355 
shade of purple and azure, rises a vertical comb, the upper 
border of which sparkles with fiery red. This beautiful float 
has a small opening at either 
end, and strong muscular 
walls, so that by their con- 
traction its cavity can be con- 
siderably diminished. And 
thus partly by the escape of 
air forced out through the 
Openings, and partly by the 
compression of what remains, 
the specific gravity is so much 
altered as to admit of the 
animal’s sinking into the 
deep when danger threatens. 
v 
% 
4 
+ 
i) 
i 
Numerous polyps proceed ‘ ae 
from the lower surface, ac- Ai 
companied by tentacles hav- 6 ( 
ing a sac-like extension at he ; 
their base, and hanging down ‘ ‘ 
in beautifully blue and violet ) 
coloured locks or streamers. / 
When fully extended, these = 
tentacles form fishing lines eee 
fifteen or sixteen feet long, Physalia caravella—(Considerably reduced.) 
which, as their thread-cells * Pneimatophore, oc deat paddies a. Pclypites. 
are uncommonly large, at 
once paralyse the resistance of the fish or cephalopod they meet 
with. Then rolling together, they convey the senseless prey to 
the numerous mouths of the compound animal, which, sucking 
like leeches, pump out its nutritious juices. In this manner the 
greedy physalia devours many a bonito or flying-fish of a size 
far superior to its own, and such is the corrosive power of 
its tentacles that even man is punished with excruciating 
pains when heedlessly or ignorantly he comes within their reach. 
‘ One day,” says Dutertre in his “ History of the Antilles,” ‘as 
I was sailing in a small boat, I saw a physalia, and as I was 
anxious to examine it more closely, I tried to get hold of it. 
But scarcely had I stretched out my hand when it was suddenly 
enveloped by a net of tentacles, and after the first impression of 
