MARINE AQUARIA 



Pentactafrondosa, (Jaeg.), or Brown-Sea-cucumber is the largest com- 

 mon Atlantic species which measures from a few inches to a foot in length 

 when extended. Holothuria princeps and H. floridana, the Florida Sea- 

 cucumbers, are large species which have been collected and dried for 

 export to China. 



Feather Stars and Stone Lilies. This class of Crinoidea inhabit 

 deep water where they form branching featherlike and flowerlike beds. 

 Some are permanently attached, others become detached and float about 

 by movements of the raylike arms. They are rarely found on the shore 

 and fail to survive in aquaria. 



Crustaceans. The larger Marine crustaceans are divided into a 

 number of groups, the Branchyura or true Crabs, the Anomoura or Her- 

 mit Crabs, etc., the Macroura or Lobsters and Shrimps, the Xiphosura or 

 King Crabs, the Squillidas or Mantis Shrimp, the Cirripedia or Barnacles 

 and Tops; and the smaller Marine Entomostraca or Water Fleas. 



These will be mentioned in this order. 



Callinectes hastatus, (Ord.), or Common Edible Crab, Blue Crab, 

 Sea Crab, has the shell or carapace about twice as broad as long, and 

 armed with a distinct projecting spine and eight short acute teeth on each 

 side, gradually increasing in size towards the eyes. There are four un- 

 equal-sided teeth between the eyes and a median spine, beneath. The 

 front limbs, bearing the claws, are similar to each other in form, and the 

 three succeeding pairs of legs are slender, terminating in sharp points, and 

 the posterior pair end in expanded oval joints for swimming. The cara- 

 pace grows to a length of 3 inches and a breath of 5 J^ to 6 inches, and is 

 covered with minute granulations and margined with fine hairs. The 

 upper surface is of dark-green or bluish color, the lower dusky-white, the 

 feet and claws blue, tipped with yellowish-red. The period of spawning 

 and shedding extends over several months. It is very active, crawling and 

 swimming rapidly, and may be taken on muddy and sandy bottoms in 

 both salt and blackish water, from Cade Cod to Florida. It is predace- 

 ous and feeds upon all living and dead animals. This species may be 

 distinguished by the sharp spine on each side of the carapace. There are 

 four other species of this genus in more southern waters. 



Carcinus mienus, (Say), or Green Crab, has a bright green color varied 

 with spots and blotches of dull yellow and brown, and has the carapace and 

 limbs more or less granulated. It has heavy claws and legs shorter than 

 the foregoing and shorter spines at the sides of the narrower carapace, with 

 four unevenly cirrated teeth at each side and three between the eyes. The 

 last pair of legs also nearly resemble the other three pairs and lack the 

 broad swimming blades of the foregoing species. Abundant between tide- 



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