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"...With an animation quite unusual for them at other times, one of the snails unfolds from the right side of its neck, where the reproductive opening original: "generative orifice" is located, a wide small sac original: "sacculus". This sac, by turning inside-out, displays a sharp, dagger-like dart original: "speculum" attached to its walls. Having bared this singular weapon, the snail endeavors, if possible, to strike it into some exposed part of the other snail’s body. The other snail, in response, takes every precaution to avoid the blow by quickly retreating into its shell.
But, at length, having received the sexual wound, the struck snail prepares to retaliate, and in turn makes every effort to puncture its attacker in a similar manner. The darts are generally broken off in this encounter and either fall to the ground or remain fixed in the wounds which they have inflicted. After these preparatory stimulations, the snails proceed to more effective advances. The sac of the dart is withdrawn into the body, and another small sac original: "sacculus" is pushed out from the shared reproductive opening by a similar process. Upon this second sac, two openings are seen: one connects with the female reproductive system of the animal, while from the other a long, whip-like thread original: "filament"—the male organ—is gradually unfolded. It turns inside-out like the finger of a glove until it reaches a length of an inch or more. Then, each of the two snails fertilizes the other and is itself fertilized at the same time."
Even in hermaphroditism the condition of having both male and female reproductive organs, however, the female element is the dominant one, being more extensively concerned with the reproductive and generative processes. Meanwhile, the male element apparently exists merely for the purpose of energizing, or stimulating the female element into creative activity. As we move up the scale of biological complexity, the male individual apparently becomes specialized for the convenience of forming unions with female organisms that are physically separated from the original female. In all things related to the creation and reproduction of life, the "mother-element" is the primary and dominant force.