Heredity and sex . efore onlytwo of them can be present in any one individual, andsince they are allelomorphs they will pass into differentgametes. The order of dominance is Achates, Agenor,Laomedon. The male carries these same factors, butthey are not effective in him. Baur accounts for theresults in a somewhat different way, but involving or-dinary Mendelian conceptions. An interesting case is that reported by Foot andStrobell. They crossed a female of a bug, Euschistusvariolarius, the male of which has a black spot on theend of the body (the female lacking the spot), with amale of Euschistu
Heredity and sex . efore onlytwo of them can be present in any one individual, andsince they are allelomorphs they will pass into differentgametes. The order of dominance is Achates, Agenor,Laomedon. The male carries these same factors, butthey are not effective in him. Baur accounts for theresults in a somewhat different way, but involving or-dinary Mendelian conceptions. An interesting case is that reported by Foot andStrobell. They crossed a female of a bug, Euschistusvariolarius, the male of which has a black spot on theend of the body (the female lacking the spot), with amale of Euschistus servus that lacks the spot both inthe males and the females (Fig. 77). The daughtershad no spot; the sons had a faint spot, less developedthan in variolarius. When these (Fi) offspring wereinbred, they obtained 249 females without a spot. 152 HEREDITY AND SEX 107 males with a spot (developed to different degrees),and 84 males without a spot. The authors give noexplanation of their results — but they use the re-. FiG. 77. — To left, in 1, is male of Euschistus variolarius, to right male ofE. servus. 2 and 3 show eight F2 males; 4 shows seven F2 males fromanother mating. suits to discredit some of the explanations, that reston the assumption that the chromosomes are the chieffactors in Mendelian heredity. I venture, neverthe-less, to suggest the explanation shown on the accom- THE EFFECTS OF CASTRATION 153 panying diagram (Fig. 78). The analysis rests on theassumption that neither one nor two doses of S in thefemale is able to produce a spot, while in the male onedose of S suffices. E, sctyui 5 X 5 X 5X — S E,. S X 5 X SpoTlcss^ $ »?..$ SX $X S 5 X ShJT ar # SX—s QtktncHi^ of SX—5 X SX — s X-5 —5 SXSX^ SSX sKd SXs X5 X SX > Spo\\^h^ $ SsX SK^ ez. 5X5 xj S S X spot tT S 5 X spot qT s 6 X Sfof qT s 5 X SJvflciS cT Fig. 78. — Diagram showing a possible interpretation of the heredityof spot of male when E. servus is crossed wit
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Keywords: ., boo, bookcentury1900, bookdecade1910, booksubjectsex, bookyear1913
