LINKAGE STUDIES IN TRIBOLIUM CASTANEUM HERBST. IV. FURTHER DATA ON THE POSITION OF "TRUNCATED ELYTRA"

Abstract

Additional three point crosses establish the te (truncated elytra) gene 24 units to the right of pd (paddle), on the other side of sp (spotted) which is 46 units to the left of pd. A revised map of the X chromosome bearing six points is given. A coefficient of coincidence of .92 has been calculated indicating crossing over in the te-pd region has little or no effect on crossing over between pd and sp. However, an effect of maternal age in crossing over has been observed in the te-pd region when broods I and HI (each brood collected at four-week intervals) are compared, a finding which requires further investigation. The belief that the r and te genes in T. castaneum and Latheticus oryzae Waterh, are homologous is reiterated in spite of certain differences in the physiological behavior and the relative distances of the two genes in the X chromosomes.