. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. EFFECT OF AGE IN SECONDARY NON-DISJUNCTION. 125 number of white and apricot females obtained by equational non- disjunction from the white-apricot stock, females of which pro- duced XXY daughters pure both for white and for apricot. I could not observe that these allelomorphs, white and apricot, dif- fered from one another in the capacity for exceptional production, in comparable experiments. The culture methods in this latter part of the work were modi- fied somewhat. Yeast-seeded banana agar was used for food. Females whic
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. EFFECT OF AGE IN SECONDARY NON-DISJUNCTION. 125 number of white and apricot females obtained by equational non- disjunction from the white-apricot stock, females of which pro- duced XXY daughters pure both for white and for apricot. I could not observe that these allelomorphs, white and apricot, dif- fered from one another in the capacity for exceptional production, in comparable experiments. The culture methods in this latter part of the work were modi- fied somewhat. Yeast-seeded banana agar was used for food. Females which were producing young were left continuously in the incubator except during the interval when they were changed to a new culture. Subcultures were made up every six days, at 20 or 21 degrees C., and every three days (in group 6, Table III., every four days) at temperatures higher than this. Two Freis electric incubators and one electrically controlled cabinet incubator was used and the temperature checked daily. These machines will fluctuate in temperature, within a degree up or down, but since the' routine involved the growth of flies, at each different temperature, over a considerable period of time such fluctuations should cancel out. Table II. summarizes and Fig. I depicts graphically the results obtained when groups of females were kept continuously at cer- tain temperatures each female being transferred to new subcul- ture vials as long as she remained fertile. Except in groups 6 and 7, in which inbreeding was the rule, male parents came from several cultures. In group 6 one inbred stock of wild males was used, in group 7 exceptional brothers. A comparison of Tables I. and II. and of the curves in Fig. I brings to light some very obvious differences in the characteris- tics of the females in comparable groups. In group I the average fertile lifetime, in round numbers, was 28 days. In groups 4 and 5, kept at comparable temperatures, the average fertile life- time was 16 d
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
