THEIR WONDERFUL BEAUTY. 95 



ordinarily live, but which are not essential to the existence 

 of the tenant, as they can leave it without inconvenience, and 

 wander at liberty for their food elsewhere. Their bodies are 

 formed of more or less numerous rings, each of which is 

 furnished with feet, which are the chief organs of motion, 

 and are truly wonderful. They are generally in the form of 

 small tubercles, and for the most part are composed of two 

 branches. Their summit or tip is frequently armed with 

 one or more bundles of bristles, which play an important 

 part in the history of the animals. They form an orna- 

 mental appendage to the worm, and at the same time are 

 used as organs of defence and offence. Notwithstanding 

 they live in situations in which they are seldom seen by the 

 human eye, yet in some species these organs have a remark- 

 able degree of brilliancy, shining with a metallic lustre and 

 splendor of the richest kind. The common Sea-Mouse, for in- 

 stance, has a very large bundle of them attached to each foot, 

 which are -very fine and of considerable length. Gold, azure, 

 purple, and green play on their surface in a thousand reflec- 

 tions, and these rainbow colors are in perfect harmony with 

 the changing reflections and rings of the body. The wing 

 of the butterfly has not received a more brilliant dress than 

 these worms, concealed at the bottom of the waters, and 

 sometimes buried in black and fetid mud. They are bril- 

 liant as gold, and changeable to every hue of the rainbow. 

 The colors they present are not surpassed in beauty by the 

 scale-like feathers of 'the humming-bird nor by the most 

 brilliant gems. These bristles, however, are as useful as 

 they are ornamental. Surrounded on every side by enemies, 

 usually dwelling in the waters where the worms live, they 

 require powerful weapons of offence for resistance or for 

 securing their prey. 



Some species of these worms are armed with a weapon 

 like a harpoon, a lancet, or a knife. Some have an appen- 

 dage, falchion-shaped, and others a bayonet fixed upon a 



