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i he sea we may often see such a natural garden, which, 

 looked at through the crystal-clear water of a rocky coast, is- 

 really an enchanting sight, and yields to the naturalist a rich 

 booty , not only of such worms, but of many other creatures 

 that there abide. 



But not all Annelids secrete such calcareous shells or houses; 

 many kinds roll in the sand, and wet it with their slime, thus 

 forming soft sandy tubes. This is done by the Terebellae , 

 whose yellowish-red feelers may often be seen sticking out of the 

 bottom of the tank, where they turn and twist about, seeking 

 food in all directions and looking like a knot of living threads. 

 Other worms cement together little stones, bits of broken shell 

 and such small things: and others again make shells of mud, 

 or dwell in long cartilaginous tubes, open at each end, which 

 look exactly like slender penholders; for example the Onuphis. 

 This last kind belongs to those Annelids which creep about with 

 their shells, like the well-known larva of the fresh-water dragon- 

 fly; while the first-mentioned adhere to rocks, pieces of wood 

 and other fixed objects, or stick the bottom of their tubes loosely 

 into the sand. ISJany kinds are a plague to navigation, for they 

 accumulate in such masses on the keel of a ship that its motion 

 is considerably retarded. 



All these animals, when young, have an entirely different 

 form. On issuing from the egg they are larvae of a very pe- 

 culiar shape, and swim freely about. After a short time the}- 

 become fixed to some object and then by a complete metamor- 

 phosis , change into annelids and begin to secrete or make 

 their tubes. 



These tube-inhabiting Annelids , of which a great man}- 

 beautifully coloured species are to be found in all soutbern 

 seas . correspond , as a second group , to a not less rich and 

 varied group of free Annelids. The Gulf of Naples has long 

 been celebrated among zoologists as the richest in the latter 

 animals; and already, including the tube-inhabiting worms, 

 more than 300 different species have been discribed. But only 

 a small portion are fit for the Aquarium, most kinds living in 

 the mud, rocky crevices and hollo,ws, and seldom being able 

 to bear the direct influence of the light for any length of time. 

 One of the most beautiful kinds is the Sea Mouse (Aphrodi- 

 te) , the prickly coat of which has at housand metallic col- 

 ours. Its nearest relation is Hermione, which in spite of its 

 beautiful name, is a very insignificant and disgusting creature, 

 the hooked spines of which easily fall out, stick in the hand 



