Figure 1 in Evolution of spermatophore transfer mechanisms in cephalopods

Figure 1. Types of spermatophore attachment in coleoids. (A) Deep implantation (elongated spermatangium; e.g. Architeuthidae, Cranchiidae); (B) deep implantation (bulbous spermatangium; e.g. Octopoteuthidae, Sepiolidae); (C) shallow implantation (e.g. Loliginidae, Ommastrephidae, Enoploteuthidae); (D) plugged attachment (e.g. incirrate octopods). Abbreviations: ft, female tissue; ov, oviducal gland; sp, spermatangium.