Abstract
Observations during histogenesis tests of the red excretory pigments of E. kuhniella showed that some wild spp. had a red coloring of the malphigian vessels of varying intensity, which was independent of the environment. It was possible to raise pure races from the extreme variant spp. whose F2 crossgeneration implies monohybrid succession with intermediary characteristics. This ommatin pigmentation of malphigian vessels is inherited independently of the pigmentation of the testicles, eyes, mesenteron, or the shed cuticle. The allele which causes the greater pigmentation is termed "Om" and the one with contrary effects as "om.".