When most people think of marine life, they imagine fish-like
             creatures, swimming through the deep waters with a swish of the fin.
             However, there is another class of animal that uses a very different form
             of locomotion. Instead of the more common "finned" animals, these
             creatures use a kind of jet propulsion to moveâ€"a method of locomotion that
             is surprisingly effective. Two of these animals are the squid and the
             The squid is one of the fastest animals that use jet
             propulsion.[1]Indeed, the squid is so fast that it can reach speeds of up
             to 30km/h.[2] The actual mechanism by which the squid moves in this way is
             by expanding their muscular mantle and filling it with water. The animal
             then contracts this mantle, expelling the water forcefully through an
             opening known as a siphon. Interestingly, the squid controls its direction
             by changing the direction of the siphon.
             The cuttlefish uses jet propulsion as well in its locomotion by
             drawing water through its mantle opening and contracting the muscles in
             that mantle (like the squid), while making a tight seal around the head,
             allowing the water to be forced through the funnel in a jet. Further, like
             the squid, the cuttlefish can move its valve opening through which the jet
             flows in any direction, allowing it to control its direction. However, the
             Jet propulsion is a very interesting form of locomotion for marine
             life. Indeed, many consider it to be the inspiration for the modern marine
             jet engine (as well as the air jet engine). Although many forget that not
             all of the "swimming" marine animals use fins to swim, the squid and the
             cuttlefish are excellent examples of the diversity of the sea.
             [1] http://wings.avkids.com/Curriculums/Marine/dissecting_summary.html
             [2] http://www.oceanworld.com.au/factfile.asp'ID=9
             ...