European squid propulsion. The posterior border is slightly concave. The head is relatively small and has large eyes which are covered with a transparent membrane. Like almost all squid, this species has ten limbs surrounding the mouth and beak: eight are relatively short arms, and two, which form the tentacles, are long, as they are used to catch prey. The fourth left arm of males is a hectocotylus. The European squid can grow up to 30–40 cm in the mantle length, but more usually they are 15–25 cm long. The males are generally bigger than the females and exhibit more rapid rates
Bigfin squid cephalopods, the arms and tentacles were of the same length and looked identical (like extinct belemnites). The appendages were also held perpendicular to the body, creating the appearance of strange "elbows". Most remarkable was the length of the elastic tentacles, which has been estimated at stretching up to 15–20 times the mantle length. Estimates based on video evidence put the total length of the largest specimens at or more. On close ups of the body and head, it is also apparent that the fins are extremely large, being proportionately nearly as big as those of bigfin squid larvae. While they