104 



THE FAMILY AQUARIUM. 



that character. This is because, when disturbed, it 

 withdraws the tentaculse it usually displays above the 

 common surface, and retreatuig thus into its habitation, 

 loses its pecuUar appearance. The young are more 

 transparent than the old ones, and sometimes of a darker 

 color. 



The class of Zoophytes, known as the LucernaricBj are 

 not without claims to favor. The L. auricula is a light 

 pink in color, and is supposed to resemble the flower after 

 which it is named, though some naturalists pronounce it 

 more like the convolvulus. The Cam;panulata is more 

 bell-shaped, and is of a liver color. All the Lucernaric^ 

 are too frail for the Aquarium. 



The Polyjps, or compound Zootypes, may furnish us 

 with a few specimens of utility. The Pennatula fhos- 

 fhorcea^ or Sea Pea, is seen at times standing upright, its 

 bare portion or trunk, which is of a purplish red, resem- 

 bhng a quill, and its purple branches, or pinnae, standing 

 sponsor for the feathered end. When plunged into cold 

 water, it emits, in its irritation, a shower of phosphoric 

 sparks. The Alyconium digitatum (Many-fingered Ane- 

 mone), is sometimes called Dead-men's Toes by the fisher- 

 man. It looks like a mass of short fingers when the final 

 florets are closed ; and each finger-like cell contains a sepa- 

 rate being, v/hile, at the same time, each is virtually a por- 

 tion of the common body or spine that supports them all. 



The Mollusca. — The Mollusca^ as we have suggested 

 in our chapters on the Fresh-water Aquaeium, perform the 



