364 Gates. 
F, 42 plants, 7 of which were O. Lamarckiana and the remaining 35 
either O. rubricalyx or O. rubrinervis. Of the latter, 12 which came 
into bloom were all O. rubricalyx. It therefore seems quite certain 
that O. rubricalyx and O. Lamarckiana are the only forms produced 
in the F, of this cross. 
The behavior of the O. rubrinervis reverts from O. rubricalyx 
was tested by a series of crosses and found to be the same as that 
of O. rubrinervis of pure pedigree. Thus O. rubrinervis (from O. rubri- 
calyx) = O. Lamarckiana gave 73 plants, of which 41 were O. rubri- 
nervis and 32 O. Lamarckiana. The reciprocal cross yielded 69 plants, 
of which 46 rosettes were probably all O. rubrinervis, 22 rosettes 
were O. Lamarckiana, and one a mutant. Also O. rubrinervis (from 
O. rubricalyx) =< O. nanella produced 77 plants, of which 25 were 
O. Lamarckiana, and the remainder (52) either O. rubrinervis or 
O. rubricalyx as shown by their rosettes. Of these 52, eleven which 
came into bloom were all O. rubrinervis. Hence it is safe to assume 
that O. rubrinervis and O. Lamarckiana are the only types in the F, 
of this cross, just as O. rubricalyx and O. Lamarckiana are the only 
types in the F, of O. rubricalyx >< O. nanella. 
O. biennis = O. rubricalyx produces twin hybrids, the O. laeta and 
O. velutina types appearing in the F, in the same way as though 
O. rubricalyx were replaced in the cross by O. rubrinervis or O. nanella, 
though the rosettes show considerable variability. 
The results of this series of pedigrees and crosses, so far as they 
can now be stated, are tabulated in the accompanying table (11). 
V. Discussion. 
The data here brought together show that while there is probably 
no inheritance of quantitative differences in anthocyan production in 
O. rubrinervis within its range of variability as represented by the 
series of buds in plate VI, figs. r—7; yet in the type O. rubricalyx 
represented by fig. 8 there is strict inheritance of a greatly increased 
anthocyan production. There is similarly evidence that, in race No. 25, 
having somewhat greater pigment production than O. rubrinervis (though 
the mode is the same) this tendency is inherited generation after 
generation. We thus find cases in which quantitative differences in 
amount of anthocyan production are inherited, and equally clear cases 
in which they are not inherited within certain limits. This condition 
of affairs is not a peculiar one, but is now known to hold for a large 
