A PORTUGUESE MAN-OF-WAR. 57 
very good idea of the delicacy and beauty of 
some of these organisms, while above the Hy- 
droids and the harp shell float what look like 
shimmering balloons, airy, fairy enough to bear 
“sylphs and fays beyond the moon.” 
These are jellyfish—JM/eduse—first pro- 
duced as buds upon the Hydroid, where they 
enlarge, until at length they become detached 
and float away. 
Some Hydroids cast upon our sea beaches 
and preserved in collections might be taken 
for seaweeds, they are so delicate, were it not 
for their horny external coverings. 
