The Lock-and-Key Hypothesis: Evolutionary and Biosystematic Interpretation of Insect Genitalia

If I see null number of keys, of very minute and elaborate workmanship, all different, I cannot doubt that every one is intended to fit some special lock . . . and this conviction is the stronger, the more varied and the more complex are the keys. We cannot withhold null hearty assent to the conclusion of one of the most eminent of modem physiologists, who, speaking of these organs in the class of Insects generally, says, They prevent allied...