I. THE RED COLOUR OF THE MESOCARP OF SEEDED 

 FRUITS IN THE PERSIMMON (Diospyros Kaki) 



II. A VISUAL METHOD FOR ESTIMATING 

 ASTRINGENCY 



FRANCIS E. LLOYD 

 McGill University, Montreal, Canada 



It has been pointed out by Mr. H. Harold Hume^ that cer- 

 tain, though not all, species of the cultivated persimmon are 

 characterized by the fact that, in the event that the fruit is pol- 

 linated, more or less of the mesocarp in the region of the develop- 

 ing seeds early takes on a reddish colour. This coloration had 

 already been noticed to occur in fruits in those species whose 

 fruit becomes non-astringent on the tree. This fact was com- 

 municated to me by Mr. George E. Roeding, of Fresno, Califor- 

 nia, in response to an inquiry prompted by my suspicion- that 

 the non-astringency in those fruits which become edible while 

 still firm and attached to the tree, might be due to the oxidation 

 of the tannin, a view which, as it eventuated, can not be sup- 

 ported in the light of all the facts. I had noticed furthermore 

 that small masses of tissue containing the red colour commonly 

 occur even in astringent fruits, that is to say, in those which 

 lose their astringency only after artificially stimulated or after 

 prolonged spontaneous ripening, following removal from the 

 tree. The occurrence of seeds is therefore not a conditio sine 

 qua non for the production of the colour, although, as Mr. Hume 

 has said, it occurs regularly in the seeded fruits of certain kinds 

 in such amount and constancy that the presence of the seeds may 

 be suspected of having some connection with it. Further support 

 for this conclusion came to my attention in 1911 and 1912. In 



1 A Kaki classification. Journal of Heredity, 5: 400-406, 1914. 



2 Lloyd, F. E. The induction of non-astringency in persimmons at supranor- 

 mal pressures of carbon dioxide. Science, 11. 37: 228-232, Februarj^ 7, 1913. 



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