Editing Hectocotylus (section)

{{short description|Cephalopod sex organ}}
[[File:Hectocotyle1.jpg|thumb|160px|[[Georges Cuvier]]'s original illustration of an octopus hectocotylus, which he named ''Hectocotyle octopodis'']]
A '''hectocotylus''' ({{plural form}}: '''hectocotyli''') is one of the [[cephalopod limb|arm]]s of male [[cephalopod]]s that is specialized to store and transfer [[spermatophore]]s to the female.<ref name="HanlonMessenger2018">{{cite book|author1=Roger T. Hanlon|author2=John B. Messenger|title=Cephalopod Behaviour|url=https://books.google.com/books?id=oppPDwAAQBAJ&q=hectocotylus|date=22 March 2018|publisher=Cambridge University Press|isbn=978-1-108-54674-4}}</ref> Structurally, hectocotyli are [[muscular hydrostat]]s. Depending on the species, the male may use it merely as a conduit to the female, analogously to a [[penis]] in other animals, or he may [[Autotomy|wrench it off]] and present it to the female.

The hectocotyl arm was first described in [[Aristotle's biology|Aristotle's biological works]]. Although [[Aristotle]] knew of its use in mating, he was doubtful that a tentacle could deliver sperm. The name ''hectocotylus'' was devised by [[Georges Cuvier]], who first found one embedded in the mantle of a female [[Argonaut (animal)|argonaut]]. Thinking it to be a [[helminths|parasitic worm]], in 1829 Cuvier gave it a [[name of a biological genus|generic name]] (''Hectocotyle''),<ref>{{cite book|author-link=Armand Marie Leroi|author=Leroi, Armand Marie|title=The Lagoon: How Aristotle Invented Science|date=25 September 2014|publisher=Penguin |isbn=9780698170391|url=https://books.google.com/books?id=-DVBAwAAQBAJ&q=aristotle+hectocotylus&pg=PT80}}</ref><ref>{{cite book|author-link=D'Arcy Wentworth Thompson|author=Thompson, D'Arcy Wentworth|year=1913|title=On Aristotle as a biologist, with a prooemion on Herbert Spencer|series=Being the [[Herbert Spencer]] Lecture before the University of Oxford, on February 14, 1913|publisher=Oxford University Press|page=19}}</ref><ref>{{cite book|author1=Nixon M.|author2-link=John Zachary Young|author2=Young J.Z.|year=2003|url=https://books.google.com/books?id=BRvrtsuKc6MC&q=hectocotylus|title=The brains and lives of Cephalopods|publisher=Oxford University Press|isbn=9780198527619}}</ref><ref>{{cite web|url=https://www.gbif.org/species/3246735|title=GBIF:Hectocotylus Cuvier, 1829|access-date=21 November 2016}}</ref>
which is a New Latin term combining the Greek words for "hundred" (''hec(a)to(n)'') and for "hollow thing, cup" (''[[cotyle]]'').