Comb Jellies

Comb Jelly

You cannot go diving in New Jersey waters without seeing Comb Jellies. Up close, rainbow-like rows of tiny beating hairs called cilia may be seen - the Comb Jelly's only means of propulsion. Comb jellies do not sting, but they are still voracious predators, feeding on anything they can engulf. At night they may phosphoresce - watch the boat wake as agitated Comb Jellies flash in the dark like depth charges. Cnidarians are exclusively marine, although some are tolerant of brackish water as well.

Leidy's Comb Jelly
Leidy's Comb Jelly - Mnemiopsis leidyi

About two inches wide, Leidy's Comb Jellies range from Cape Cod to the Carolinas and are common in the Chesapeake Bay as far north as Baltimore. They have eight moving comb plates that move food toward the mouth. Marine labs use them to study bioluminescence and regeneration. Comb jellies are not true jellyfish - they have no stinging cells, although they are predatory, and have even been known to take small fishes!

Ovate Comb Jelly
Ovate Comb Jelly - Beroe ovata

Comb Jellies are classed in a phylum of their own - Ctenophora. ( Pronounced 'tee-no-for-a', the C is silent. ) It has about 100 species in 5 orders. Comb Jellies live in all oceans, not caring whether it is hot or cold. Reproduction is sexual. The young resemble their parents and they can breed as soon as they hatch at just 1mm in length!

Sea Gooseberry
Sea Gooseberry - Pleurobrachia pileus

The Sea Gooseberry is another ctenophore like the Comb Jelly. Although they have tentacles, these creatures do not have stinging cells; instead, the tentacles use a sticky coating to trap plankton.

comb jelly
Herb Segars Photography

aluminum tanks

Scuba tanks are made out of steel or aluminum. Aluminum is cheaper and has somewhat better corrosion resistance, but steel is stronger. The "standard" modern scuba cylinder is the aluminum "80", which actually holds about 77 cubic feet of air at its rated pressure of 3000 psi. This type of tank has probably caught on because for an average-sized person with reasonably good breathing skills, this size is just big enough to cover your allowable no-decompression bottom time and no more. For smaller people, 63 cubic foot aluminum tanks are available, while for larger folks there are choices as big as 120 cuft.

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