On a Periodic Structure in Many Insect Scales, and the Cause of Their Iridescent Colours

摘要: Ever since the distinction between pigmentary and structural colours of insects was recognised, there has been discussion as to cause latter phenomenon, but no satisfactory explanation yet given. A great variety theories suggested, very unsatisfactory controversial state problem may be gathered from Prof. R. W . Wood’s statement in a recent paper,* effect that not only are existing inadequate explain phenomena, these “ cannot explained by any common laws Optics with which we familiar.” The have advanced account for metallic fall under following headings :—• (1) diffraction light at surface grooved structure or grating.” (2) interference surfaces thin films,” either single multiple. (3) scattering shorter light-waves bodies composed particles smaller diameter than waves themselves, allow longer red pass unhindered. blue sea, snow, sky is this nature. It sometimes called due small particles,” expression will adopted paper.