A small green alga (up to 30 cm across) with a broad, crumpled frond that is tough, translucent and membranous. It is attached to rock via a small hold-fast .
Paolo Pizzolla 2008. Ulva lactuca. Sea lettuce. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 08/12/2010]. Available from: