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STUDIES IN SEEDS AND FRUITS 



Cassia fistula. — The Shrinking and Swelling Regime of a Seed of 

 Cassia fistula in Illustration of the Mode of employing the 

 Data in the above Table as described on the preceding Page. 



SUMMARY 



(i) In order to illustrate the shrinking and swelling regime of a 

 seed, a comparison is made of the relative weights of the coats and 

 kernel in the three conditions : the pre-resting, the resting, and the 

 swollen state preceding germination (p. 187). 



(2) In connection with the requisite data the proportional weights 

 of the coats and kernel of the resting seed are first dealt with, results 

 being given for thirty-nine species of leguminous seeds and for forty- 

 three species belonging to twenty other orders, including Anonaceae, 

 Convolvulaceae, Euphorbiaceae, Malvaceae, Sapindaceae, Sapotaceae, etc. 

 For convenience only one value is generally employed in the discussion, 

 that of the relative weight of the coverings, which is termed the " seed- 

 coat ratio" (p. 188). 



(3) Respecting the great range in the proportional weight of the 

 coats of the resting seed, it is shown that although the range is 

 from 5 to 69 per cent, of the seed's weight, nearly the whole of it 

 is presented by the leguminous seeds, and that the maximum of 

 the range is but slightly extended in the case of seeds with abundant 

 hairs (p. 189). 



(4) By grouping the results for the eighty-two species, it is found 

 that the average weight of the coats of the resting seed is about 30 

 per cent, of the total weight, rather below for leguminous seeds and 

 rather above for seeds of other orders. Excluding very small seeds, 

 " size " has little or nothing to do with the ratio (p. 191). 



(5) As regards the constancy of the seed-coat ratio within the 



