A POETUaUESE MAN-OF-WAE. 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 

 shimmeriug balloons, airy, fairy enough to bear 

 " sylphs and fays beyond the moon." 



These are jellyfish — Medusoe — 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. 



