On Germinal Selection as a Source of Definite Variation

Presented at the inaugural meeting of the International Congress of Zoologists in 1895, this influential essay tackles a long‑standing puzzle in evolutionary biology: how organisms acquire the specific variations needed for natural selection to act upon them. The author argues that, beyond random mutations, an internal “germinal selection” process shapes the direction of variation, aligning it with the organism’s environmental circumstances. By framing this mechanism as a necessary complement to Darwinian selection, the work seeks to dissolve the apparent contradiction between accidental variation and adaptive fitness.

The paper also engages with contemporary critics of heredity theory, acknowledging the imaginative nature of scientific models while defending their explanatory power. Drawing analogies to Maxwell’s mechanical constructions in physics, the author shows how speculative yet rigorous frameworks can lead to concrete insights. Readers will encounter a thoughtful blend of experimental observation, theoretical reasoning, and historical context that marks a pivotal moment in the early debate over how evolution operates.