MARINE AQUARIA 



form and size, and specimens from different localities would scarcely be 

 recognized as of one and the same species. 



Anomia simplex (Orb.), or Jingle Shell, or Jingle, has rounded, scaly, 

 variously wrinkled and undulated, ^ inch in diameter valves. The shells 

 are a common feature on the seashore, their fine pearly lustre and flattened 

 form distinguishing them from other oysters and clams. It is a hardy 

 species found abundantly on oyster beds and adhering to fixed objects 

 along the Atlantic coast. 



Marine Molluscs as Scavengers. Marine Univalves feed upon 

 plants and animals, more particularly the lower forms, algae, oscillaria, pro- 

 tozoans and hydroids. In the aquarium they perform useful purposes, 

 keeping the glass clean and devouring food particles which might contam- 

 inate the water. They are not quite as good scavengers as some of the 

 freshwater species. Bivalves also render good service in keeping the 

 water clear, but only a few should be introduced, as they require consider- 

 able water for respiration and to obtain sufficient of the minute vegetable and 

 animal life upon which they feed. 



Squids. Two of the Squids may be mentioned, as they are common 

 along almost the entire Atlantic coast. These are Ommastrephes sagittatus 

 (Lam.), and Loligo pealii, (Les.), both from 6 to 12 inches long. All the 

 family are ferocious creatures, the tyrants of the lower orders ; solid fleshy 

 animals having powerful arms furnished with rows of cup-like suckers,strong 

 jaws and membranous tongues, armed with recurved prickles. They dis- 

 charge an inky fluid through a siphon. The beak or pen is the cuttle-fish . 

 bone of commerce and forms the skeleton of the animal. 



Chordata. These animals are common on marine plants, submerged 

 woodwork and other fixed objects. Their characteristic of ejecting jets of 

 water secured for them their popular name of Sea-squirts. They are 

 usually of dull colors except in southern waters, and are either individual 

 or compound animals. The common species are: 



Molgula manhattensis, (Say), a very general form, has an olive-green 

 globular body with slightly rough surface, about ^ inch diameter. Two 

 siphon tubes extend above the upper end. Found on seaweed, etc., either 

 singly or in clusters. 



Cynthia partita, (Say), another common form, has an oblong body, 

 one inch in diameter, of rusty brown color, marked with red and purple. 

 Usually found on piles or flattened under stones. 



Botyllus gouldii, (Stimp.), is a generally distributed compound form 

 which appear as thick incrustations and bands on plants and piles. There 

 are many other common forms. Individual Sea-squirts will survive in 

 smaller aquaria, but it is not advisable to introduce the compound forms. 



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