MARINE AQUARIA 



The most common and generally distributed Middle Atlantic coast 

 forms are : 



Metridium marginatum, (Les.), having a smooth, cylindrical, light- 

 brownish column with deeply folded and fringed margin, and numerous 

 short, fringelike tentacles, of which the central are the longest. The 

 color is variable, the disc usually a light flesh-color and the tentacles grey- 

 ish with brighter colored tips. "When expanded it is sometimes ten inches 

 across the disc, and when contracted appears as a broad flat cone. This 

 is the most conspicuous and abundant form, found from low-water marks 

 to 90 fathoms, on piles, bridges, submerged woodwork, etc., and in rock 

 crevices and under stones, from Cape Hatteras northward. 



Eloactis producta, (Stimp.), has rows of suckers the entire length of 

 the column. It can expand to a length of 12 inches, but is usually 

 shorter and thicker. There are twenty tentacles about the margin of the 

 thick disc. The colors are variable but usually in dusky tones with 

 brighter shades and mottlings. Found from Cape Cod to the Carolinas, 

 on sandy beaches and under rocks at low-water marks ; or buried under 

 the sand with the mouth and tentacles only above the surface. One other 

 form, Ilyanthus Uvis, (Stimp.), is found south of the Carolinas to Flor- 

 ida. These are nearly related to the numerous genus Halocampa of 

 Europe, of which there are two American species, both north of Cape Cod. 



Aulactinia capitata, (Ver.), has a 6-inch long dark-grey or bluish col- 

 umn, 1 1^ inches in greatest diameter when extended, and 96 tentacles in 

 four rows about a rose-colored disc. Found at low-water marks from Cape 

 Cod to Florida. There are other deep-water species of this genus. 



Cerianthus americanus, (Ver.), a very long and slender form, has an 

 18 to 20 inches long column tapering from the disc to the base, which can 

 be contracted to 8 inches. The 124 marginal tentacles are 1 1/^ inches in 

 diameter across the disc, when expanded. Found in shallow water from 

 Cape Cod to Cape Hatteras. 



Talia crassicornis, (Gosse), has a short and thick i ^ to 2 inches 

 high column when extended, and short, thick tentacles. The colors of 

 the disc are brilliant in varying shades of bluish-green mottled with crim- 

 son, often bright cherry-red. The tentacles are somewhat lighter in color, 

 usually grey and flesh-colored. It is voracious and will entrap small 

 fishes, crabs, etc., that come into contact with the disc and tentacles. 

 Found in shallow water from Massachusetts northward on ledges and in 

 tide-pools. 



Edwardsia sipunculoides, (Stimp.), has a slender, brownish, truncated i 

 to 1% inch long column, and 24 to 30 short tentacles about a narrow 

 disc, usually of a dull grey or pinkish color. Another form, E. lineata. 



