Vitamin C and Chromosome Number in Rosa

WE were interested in Dr. Darlington-s note¹ dealing with the possible correlation between polyploidy and vitamin C content in Rosa, since we supplied a not inconsiderable amount of the material upon which the chemical determinations of Pyke and Melville² were based. Moreover, these examinations were made upon the same series of plants as we³ had used in cytological investigations carried out some years ago. Naturally, when Pyke and Melville were good enough to send us the results of their work on our material, we made attempts to link their figures with the known chromosome numbers of the bushes concerned. This proved a complete failure, for such correlation as existed lay obviously between the period of ripening of the species involved and the proportion of ascorbic acid it bore; the earlier the form ripened, the higher the vitamin content. This observation we⁴ have already published elsewhere.