Hectocotylus
![Georges Cuvier's original illustration of an octopus hectocotylus, which he named](/Images/godic/202501/17/Hectocotyle14813.jpg")
![SquidOctopod](/Images/godic/202501/17/Hectocotylized_arm_of_a_squid4813.jpg")
![](/Images/godic/202501/17/Hectocotylized_arm_of_an_octopod4813.jpg")
![](/Images/godic/202501/17/Abraliopsis_morisi_hectocotylus-English4814.jpg")
A hectocotylus (plural: hectocotyli) is one of the arms of male cephalopods that is specialized to store and transfer spermatophores to the female. Structurally, hectocotyli are muscular hydrostats. Depending on the species, the male may use it merely as a conduit to the female, or he may wrench it off and present it to the female.