158 POPULAR HISTORY OF THE AQUARIUM. 



tliey also crawl by drawing up their bodies in the same 

 manner as the worms do. The bodies are always, in their 

 normal form, cylindrical, but generally taper towards the 

 extremities. They have a mouth at the anterior extremity, 

 which is surrounded by ten feathered or branched tentacula, 

 which can be withdrawn into the body, and are sometimes 

 for days not exserted. They also have a circle of teeth in 

 the mouth. * 



In Mr. Lloyd's collection, I had the pleasure of watch- 

 ing a number of very fine specimens of Peutacfa pentactes 

 (Plate X. fig. 2, 3), which are all white with the exception 

 of their heads. These, when protruded, are sometimes found 

 to be yellowish, and sometimes blackish ; they are beauti- 

 fully branched, and, when partially expanded, look like 

 miniature bunches of grapes. The body, as the name im- 

 plies, is divided into five sides, with a double row of suckers 

 on eacli angle. These curious creatures move freely about 

 the tanks in which they are confined, assuming various 

 shapes, and seeking various positions. Sometimes they 

 crawl up the glass sides of the vessel, where they maintain 

 their hold by means of the suckers, which always adapt their 

 length to the space they have to reach over. Sometimes 

 they travel on the ground among pebbles, or wind their 



