Sea Lettuce (IMAGE) University of Gothenburg Caption Sea lettuce, which is a type of green alga, grows along the coasts and is interesting as potential food source. A new survey shows that there are 20 different species of sea lettuce along the Swedish coast. Credit Sophie Steinhagen Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.