"The time has come,"/ the Walrus said,"/To talk of many things:/Of shoes--and ships--and sealing-wax--/Of cabbages--and kings--/And why the sea is boiling hot--/And whether pigs have wings." Lewis carrolBack in the days Dearest had an oyster farm & periodically our kitchen would be alive with blue~ringed octopi. Now my kitchen is no place for blue~ringed octopi. Despite the fact that my brothers used to keep these things in a salt water tank [whence they escaped & roamed the house to be found months later dried up & shriveled in obscure corners] I am not particularly fond of octopi. One of these little beauties can kill you in a matter of minutes & by the time you see the beautiful blue rings it is probably too late. There is no cure for the choice little chemical [tetrodotoxin] the blue~ringed octopus' salivary glands produce. Chances are you will never even see it until you've stepped on it. It's a rather dull brown colour normally. I believe tetrodotoxin is similar to the chemical in puffer fish ~ which is why you shouldn't eat them either.
However octopi are interesting. For one thing they are smart. They're up there in the chain of things that don't have backbones with a well developed brain. In California in 2009 an octopus pulled on a valve & flooded the Santa Monica Pier aquarium & they've been filmed opening jars that have food in them. They've got their priorities right; food first.
Certain things about octopi have become pretty well known ~ mouth like a parrot's beak, blue blood, & 3 hearts [1 to pump blood round the body, 1 each to pump blood through each gill.] but did you know each tentacle has its own brain, all co~ordinated by a centralized brain in the head? Gives a whole new dimension to multiple personalities!
A mature female Giant Pacific Octopus has an amazing 28o suckers on each tentacle, will mate just once [ really weird mating habits which are far too gross to discuss on a family friendly blog] & won't eat while guarding her 150 000 eggs ~ which may account for her then dieing. The blue~ringed octopus' clutch only contains 50 eggs, which is a pretty good thing. I know they're rare & they're pretty but they remain one of the most venomous & deadliest things on the planet. Strangely blue~ringed octopi aren't recommended pets for salt water tanks. Wonder why?