Echinodermata - "Spiny Skin"
Starfish
Starfish reproduce by female starfish releasing their eggs and then male starfish populating the area with their sperm. Once the egg is fertilized the larvae of a starfish floats to the water surface for a few weeks and then drop to the ocean bottom and begin to take a starfish form. Many think this is also not just reproduction of the starfish, but a form of regeneration as well.
Sea Cucumbers
Male and Female Sea Cucumbers reproduce through the process of spawning. They each release sperm and egg cells into the water around them. Only a small amount of the eggs and sperm will become fertilized because this is done in the open water. After about 3 weeks of the fertilized eggs floating in plankton, the eggs float to the bottom of the sea floor.
Sea Urchin
Sea urchins are mass spawners. Within a given area, spawning occurs simultaneously, possibly triggered by chemical cues in the water such as a growth of plankton suitable to support the food needs of newly hatched larvae. Sea urchins are external fertilizers: First, the males release their sperm. Then, the female sea urchins release several million tiny, jelly-coated eggs. When sperm and eggs touch, the sea urchin egg becomes fertilized. According to a large farmer of sea urchins, between 60 percent and 90 percent of the total gonad contents are lost during spawning.
Sand Dollar
When reproduction occurs, gametes are released into the ocean by the sand dollars. These become free-swimming larvae, which can drift many miles with the current. The swimming larvae will go through several different metamorphoses before taking on the well-known sand dollar appearance.
Mark Mostarac