GABRIELLE L. C. HOWARD, 103 



9. COROLLA. 



As regards the corolla the following measurements were 

 made on both parents, the Fi and Fa generations in the cross 

 Type 9 x Type 51 — length of the flower, length of the individual 

 petal, maximum breadth of the petal, basal breadth of the 

 petal, breadth of the corolla tube and breadth of the funnel. 

 The results observed were similar to those obtained in the leaf 

 characters. The intermediate nature of the Fj was perfect 

 even to the method of pollination. The F, generation gave a 

 series covering the limits of both parents. The full data are not 

 given here as they present no new features, but a graphic 

 representation is given in Plate XXV. Want of time made 

 further measurements in the F3 and F4 generations impossible. 



The difference in the colour of the corolla in this case 

 was probably due to two factors. The F, generation could be 

 divided into more than three groups, and those classified as 

 white formed one quarter of the whole, forty-five plants out of 

 117. The large number of gradations obtained in the F2 

 generations indicate that this is probably not a simple 3 : 1 

 ratio, but that some of the palest pink combinations were 

 indistinguishable from white. 



