A. American lobster, Homarus americanus, with very mild epizootic shell disease lesions. Two circular lesions are indicated by arrows. B. Nine artificial lesions imposed on a live lobster carapace using a drill press serve as models of the lesion process. The flux of ions derived from the dissolving shell is followed measuring differential concentrations over short distances with the specific ion electrode technique (SIET). The lesions in B are separated by the mid dorsal suture. The 5 upper, more melanized, lesions were produced 1 month earlier than the bottom 4 lesions.
