How to Spawn an Urchin
© 1997 Chris Patton, Stanford University

A 2cc syringe filled with 0.5M potassium chloride is inserted into the sea urchin between the teeth and the hard outer shell. A small amount of potassium chloride is injected into the urchin on each side (amount varies with size of urchin, 0.1cc/inch/side). This induces the urchin to spawn if it has any eggs or sperm left.

WARNING: Only teachers should do this. Potassium chloride is potentially lethal if used improperly.