Overview of the early larval development of
. During the first five days of development, embryos of L. stagnalis undergo drastic changes in size (A-E, images are to the same scale shown in E), tissue composition (F-J) and form all main larval structures (K-O). Indicated are the positions of the apical plate (ap), the eye (ey), the foot lobe (fl) or foot (f), the developing mantle margin (mm), the prototroch (pt), the shell (s) and the blastopore (bp) or stomodaeum (st). All ages are indicated in hours post first cleavage (h). F-H and K-M are ventral views with scale bars representing 50 μm. I, J, N and O are lateral views with scale bars of 100 μm. The scale bar in panel E is 500 μm. Panels I, J, N and O are reflected about the vertical axis for consistency of presentation.