brown animal with white and black polka dot hair

Octopuses vary greatly in size: the smallest, O. arborescens, is about 5 cm (2 inches) long, while the largest species may grow to 5.4 metres (18 feet) in length and have an arm span of almost 9 metres (30 feet). The typical octopus has a saccular body: the head is only slightly demarcated from the body and has large, complex eyes and eight contractile arms. Each arm bears two rows of fleshy suckers that are capable of great holding power. The arms are joined at their bases by a web of tissue known as the skirt, at the centre of which lies the mouth.