R. P. Gregory 109 



the recessive kind of green stigma, all the offspring resulting from its 

 mating with "Orange King" having coloured stigmas^ As was to be 

 expected from the origin of the pale- pinks, none of the offspring showed 

 the colour characters of " Orange King," the stem-colour being always 

 purplish-red, and the colours of the flowers those of types found in 

 "Crimson King " F,'s (Plate XXXI, figs. 33, 36, 39, 41, 43). The pale- 

 pink strain " Reading Pink," crossed with " Orange King," gives a red 

 (Plate XXX, figs. 15, 16) rather towards the magenta side of the class 

 and having purplish-red stems. 



(2) Full colours. 



Salmon-pink. The race of this colour which has been used for 

 experiment was derived from a heterozygous crimson, or crimson- 

 magenta, which threw forms like itself, together with salmon-pinks and 

 blues. The crosses in which this race has been tested give very simple 

 results, since the race was pure for the light colour, and was without 

 factors producing, the minor variations of tint. Heterozygous salmon- 

 pinks may throw pale-pinks only, or whites may appear in addition ; in 

 either case the proportion of full colours in the offspring follows the 

 stem character. Crosses between such heterozygous salmon-pinks and 

 either " Snowdrift " or the pale-pink carrying magenta show the simple 

 operation of the magenta factor; crosses of this kind have given 

 44 magenta, 52 pale colours. 



Salmon-pink x " Snowdrift." The F^ from this cross is a magenta 

 with light red stems. In the F^ there were obtained, in 3 families : 



Foil coloan " Sirdsra " No ooloar in stems 



Ma^nta Salmon Magenta Salmon Pale-pink White 



57 J6 16 6 19 10 



52-3 17-4 17-4 5'8 23'3 7'8 



The expectation, given in italics, is based on the scheme already set 

 forth, namely, that the full colours represent the "Sirdars" -h a factor 

 which effects the even distribution of the colour. 



The salmon-pink is one of the few short-styled races with which as 

 yet detailed experiments upon the inheritance of colour have been 

 made', and a most interesting relation between the structural character 



' See Experiment 41/10 in the Table, p. 107. The pale-pinks used in Experiments 

 37/10 and 38/10 bad faintly coloured stigmas. 



' The obvions advantages of working with pure horticultural strains entail the 

 disadvantage of working exclasively with long-styled plants, since the short-styled form 

 is eschewed by florists. 



