1911 Encyclopædia Britannica/Autogeny

AUTOGENY, AUTOGENOUS (Gr. αὐτογενής), spontaneous generation, self-produced. Haeckel distinguished autogeny and plasmogeny, applying the former term when the formative fluid in which the first living matter was supposed to arise was inorganic and the latter when it was organic, i.e. contained the requisite fundamental substances dissolved in the form of complicated and fluid combinations of carbon. In “autogenous soldering” two pieces of metal are united by the melting of the opposing surfaces, without the use of a separate fusible alloy or solder as a cementing material.