Fig. 2. Concentration of the 60 kDa protein in ink. The 60 kDa protein is escapin from Aplysia californica and dactylomelin-P from Aplysia dactylomela, which are close homologues (Yang et al., 2005). For each species, two methods of collecting ink were used. `Ink released', ink collected from animals that were removed from the aquarium, blotted dry, handled until they inked and then ink was pipetted from the mantle cavity. `Ink from squeezed glands', ink squeezed from dissected ink glands. Values are mean ± s.e.m., N=6 animals for each group.