A couple of cool posts on Cephalove discussing the nature of memory in Octopus vulgaris: http://cephalove.blogspot.com/2010/07/short-and-long-term-memory-in.html http://cephalove.blogspot.com/2010/08/memory-observation-and-consciousness-in.html The upshot of the two posts is that there appears to be good evidence for multiphasic memory in octopuses, but also that it doesn't work exactly the way it does in humans and other vertebrates with a working-memory -> long-term-memory model. Instead, the vertical lobe appears to handle something analogous to working memory, on the scale of hours, but the long-term memory system seems to form memories entirely independently of this! And, perhaps even more amazingly, octopuses with functioning vertical lobes also experience faster memory fading! This is some crazy stuff, dudes. Highly recommended reading. Also, the latter discusses observational learning, which apparently O. vulgaris can do. Pretty neat.