
MARINE AQUARIA 

stout claws of nearly equal size. In form it very nearly resembles the 
Fiddler. 
Pinnotheres ostreum, (Say), or Oyster Crab, of which the female lives 
parasitically in the gill cavity of the oyster and the smaller male leads a free 
existence on or near oyster beds, are very unlike in appearance; the male 
having a firm carapace, dark-brown above with a central dorsal stripe and 
two white spots, and white below, with white legs and yellowish claws; 
and the thin-shelled female has a transparent whitish color tinged with 
pink ; the carapace of the adult female being about 1% inch broad and a 
little less in length. Occurs from Massachusetts to South Carolina. 
Pinnotheres maculatum, (Say), or Scallop Crab, occurs in the shells of 
some Sea Mussels and Scallops and attains somewhat larger size than the 
foregoing. The female only is parasitic, the smaller male usually lives 
among seaweeds and on the mud bottoms. Occurs most generally along 
the New England coast. 
Hippa talpoida, (Say), or Sand Bug, has an oval body about half as 
long as broad, the sides forming a nearly regular curve, giving to the ani- 
mal a buglike appearance. The tail is carried under the body and the 
eyes are placed on long peduncles. The color is translucent yellowish- 
white, overlaid with a purplish tinge on the back, sometimes mottled. 
Ranges from Cape Cod to Florida, and is known to fishermen as the 
Bait-bug. 
Limulus polyphemus, (Lat.), or King Crab, Horseshoe Crab, though 
not a true crab and belonging to the order Xiphosura, should be here de- 
scribed, as some naturalists: regard it as a low type of Crustacean, while 
others place it among the Arachnida. It has a very large carapace termi- 
nating in a spine at the posterior angle on both sides, a small abdomen 
with a long, tapering spine at its end. The basal portion of the legs serve 
as masticating organs. It is slothful in its habits and is usually buried in 
the mud and sand in the shallow water of estuaries and along the shore, 
feeding upon various smaller animals. Its range is from Maine to Florida, 
and is abundant along the shores of the Delaware Bay. Very small 
specimens have survived for long periods in aquaria. 
Crass AS SCAVENGERS. Crabs are voracious feeders and will attack 
their own species and most of the other living inmates of the aquarium. 
Only small specimens should be introduced, which serve as excellent 
scavengers. 
Homarus americanus, (M-E.), the American Lobster, is one of the 
most important food invertebrates, and has the body made up of two sec- 
tions. The anterior portion, consisting of the head and thorax, is covered 
with a carapace, and the posterior portion or abdomen is covered with six 
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