larval	A discrete phase in many species, beginning with the formation of the zygote and ending with metamorphosis.
lateral line	The tubular sensory organ of fishes located along the sides of the body. Used to perceive movements in water, changes in currents, and differences in pressure.
latitude	An angular distance measured in degrees north or south of the equator (latitude 0).
legislation	1. The act or process of making laws 2. The laws so made.
lethal	1. Able to cause or causing death 2. Of or suggesting death.
light	1. The medium of illumination that makes sight possible 2. Also called: visible radiation - electromagnetic radiation that is capable of causing a visual sensation.
limiting factor	Any environmental factor, or group of related factors, which exists at suboptimal level and thereby prevents an organism from reaching its full biotic potential.
liquid chromatography	The technique of separating and analysing the components of a mixture of liquids or gases by selective adsorption in liquids.
luminescent	Emitting light at low temperatures by any process other than incandescence.