It all depends on the species. You have the largest, Giant Pacific Octopus, or the one with the longest arms, the Long-armed Octopus. Each have a variety of arm length, and body length.
Octopus lay eggs in caves then watch over the eggs until they hatch. The mother octopus has nothing to eat in this time, and so starves to death. Her body is her offspring's first meal, but in some...