8 plants _ABC_. 22 plants _ABCc_. 45 plants _ABbCc_. 14 " _ABc_. 17 " _AbCc_. 36 " _aBbCc_. 9 " _AbC_. 25 " _aBCc_. 38 " _AaBCc_. 11 " _Abc_. 20 " _abCc_. 40 " _AabCc_. 8 " _aBC_. 15 " _ABbC_. 49 " _AabbC_. 10 " _aBc_. 18 " _ABbc_. 48 " _AaBbc_. 10 " _abC_. 19 " _aBbC_. 7 " _abc_. 24 " _aBbc_. 14 " _AaBC_. 78 " _AaBbCc_. 18 " _AaBc_. 20 " _AabC_. 16 " _Aabc_. [37] [Note that Mendel does not state the cotyledon-colour of the first crosses in this case; for as the coats were thick, it could not have been seen without opening or peeling the seeds.] The whole expression contains 27 terms. Of these 8 are constant in all characters, and each appears on the average 10 times; 12 are constant in two characters, and hybrid in the third; each appears on the average 19 times; 6 are constant in one character and hybrid in the other two; each appears on the average 43 times. One form appears 78 times and is hybrid in all of the characters. The ratios 10, 19, 43, 78 agree so closely with the ratios 10, 20, 40, 80, or 1, 2, 4, 8, that this last undoubtedly represents the true value. The development of the hybrids when the original parents differ in three characters results therefore according to the following expression: _ABC_ + _ABc_ + _AbC_ + _Abc_ + _aBC_ + _aBc_ + _abC_ + _abc_ + 2 _ABCc_ + 2 _AbCc_ + 2 _aBCc_ + 2 _abCc_ + 2 _ABbC_ + 2 _ABbc_ + 2 _aBbC_ + 2 _aBbc_ + 2 _AaBC_ + 2 _AaBc_ + 2 _AabC_ + 2 _Aabc_ + 4 _ABbCc_ + 4 _aBbCc_ + 4 _AaBCc_ + 4 _AabCc_ + 4 _AaBbC_ + 4 _AaBbc_ + 8 _AaBbCc_. Here also is involved a combination series in which the expressions for the characters _A_ and _a_, _B_ and _b_, _C_ and _c_, are united. The expressions _A_ + 2 _Aa_ + _a_ _B_ + 2 _Bb_ + _b_ _C_ + 2 _Cc_ + _c_ give all the classes of the series. The constant combinations which occur therein agree with all combinations which are possible between the characters _A_, _B_, _C_, _a_, _b_, _c_; two thereof, _ABC_ and _abc_, resemble the two original parental stocks.