Flustra Π has large distinctive Hillet? cells but G.L. is not able to fix this species. For fixation - fix with 2'5% glutaraldehyde + cacodylate or glutaraldehyde (2'5%) with Sorensen's buffer at pH6 to pH7.2. It is important that the osmolarity be that of the local seawater. G.L. will only work with anascans because decalcification causes so much shrinkage that you can't sort out the wrinkled shrunken layers from true structures. Wall muscle is continuous from the operculum in to the tentacles in Π Muscles on cardia attach to basal well.