24 DR. F. DARWIN ON THE 



When, on Aug. 16, 17 and 21, leaves were examined in the same 

 way, they did not show any striking difference in the amount of 

 starch. This may be accounted for by migration of starch to the 

 root-stocks and flower-stems having begun. Sinca. however, the 

 starch represents the surplus of assimilated matte* which has not 

 been converted into cellulose, is it not possible that in spite of 

 great activity of the chlorophyll-function there might be no accu- 

 mulation of starch because of great formation of cellulose ? The 

 final results of the experiment prove conclusively that far more 

 carbohydrates were formed by the fed plants ; therefore it is 

 almost certain that the first results obtained (July 18th) repre- 

 sent the true state of the case. The body of the chlorophyll 

 grain being protoplasmic, it is obvious that an increased supply 

 of nitrogen will favour the multiplication of chlorophyll and in- 

 crease the starch-producing power of the plant. Hence the well- 

 known effect of manure in increasing the yield of starch in many 

 seeds, roots, &c. Fraustadt* states that the starch in Dioncea 

 "diminishes with absorption of organic matter by the leaves." 

 This result may be perhaps attributed to over-feeding. 



The following Table shows that absorption of nitrogenous food 

 had by Aug. 7 produced a most decided effect. 



Table III. 



Number of Flower-stems on each side in the six plates (Aug. 7). 



Plate. Starved. Fed. 



1 16 22 



II 17 28 



III 26 32 



IV 19 25 



V 20 30 



VI 18 36 



Total 116 173 



or in the proportion of 100 : 149*1. 



It will be seen that in every plate there are more flower-stems 

 on the fed side. The above stems bore mostly ripening capsules ; 

 but as the fed plants seemed to have more actual flower-bearing 

 stems, the following Table was made on August 8. 



* *z 



inatoraie der vegetativen Organe von Dionaa musciptda^ Inaugural Dis 

 *ertation, Breslau, 1876, p. 33. 





