That's pretty much what my two dead ones looked like. I put them in a shallow bowl of water because the did not look dead but would not curl into a ball like they should have (or move in any other way for that matter). I left them in the bowls for 24 hours just in case but they never moved and I have found nothing that says they play oposum. I have been having some fun reading a few of the studies that are fully on-line but so far I have not found anyone that tank raised them (older references - early 1900's - found that some species could not be tank raised but I am discounting that because of the change in how we keep marine tanks, the longer article I am reading now did get at least one species to spawn). It does appear that each species is different in it mating time of the year, individual preferences for dormant periods, eating habits and homing ability but so far these seem like ideal candidates for tank mates octos and some added entertainment for those of us that watch dark empty tanks hoping to see our nocturnals. One slight concern is what might be harbored on the shells and I have not found any references to salinity tollerances.Here is a photo of a chiton's mouth (mouth is on the right of the photo).
Abstract Observations on mating, egg-laying and hatching of aquarium-held individuals of Octopus tetricus Gould, 1852 are described. Females were able to store viable spermatozoa for periods up to 114 days, and laid many small eggs in strings 10 to 12 cm long. The duration of embryonic development varied inversely with temperature. The newly hatched planktonic larvae were 2.5 mm long by 1.1 mm wide, but attempts to rear them were unsuccessful, the longest survival being 21 days. The females died following egg hatching.
dwhatley;130962 said:GHolland is hoping for tank bred mercs soon.