Cephalopod limb

All cephalopods possess flexible limbs extending from their heads and surrounding their beaks.

These appendages, which function as muscular hydrostats, have been variously termed arms, legs or tentacles.

Anatomically, cephalopod limbs function using a crosshatch of helical collagen fibres in opposition to internal muscular hydrostatic pressure.

Both of these structures are thick muscles, and are covered with a chitinous cuticle to make a protective surface.

[25] Cephalopod limbs and the suckers they bear are shaped in many distinctive ways, and vary considerably between species.

Arms and buccal mass of the squid Taningia danae . As in other Octopoteuthidae , the tentacles are absent in adults.
Oral view of the bobtail squid Semirossia tenera
Head and limbs of the bobtail squid Rossia glaucopis
Oral view of male Bathypolypus arcticus with hectocotylus on arm III (left)
Cephalopod suckers and configuration of suckers on tentacular club
Serrated suckers of a giant squid
Octopus arm with two rows of suckers
Octopus suckers
A deformed octopus sucker cluster
A common octopus with a forked arm that was found in South Crete, Greece