

262 



BOTANICAL GAZETTE 



[APRIL 



to contain 20-50 per cent more sugar. Plants which had been 

 allowed to dry to the wilting point several times in the course of 

 their growth and were consequently stunted to about one-half 

 normal height yielded less nectar, the average of 6 comparisons 

 being o.44mg. per 10 flowers of the stunted and 1.39 mg. per 



10 flowers of the normal. Plants grown in a greenhouse in which 

 the temperature was low and which consequently were stunted to 

 about one-third normal height, not blooming until twice the age 

 of normal blooming plants, secreted practically no nectar. 



It was noticed further that a Salvia deeply rooted in the soil 

 secreted more than one which was hampered by a small pot, and 

 that of the former plant young vigorous branches yielded more 

 nectar than old stunted ones. 



PORTION OF FLOWERING PERIOD AND AGE OF FLOWER 



Table VI illustrates the relation of nectar secretion to the part 

 of the flowering season in which the flower in question appears. 

 In all cases the compared flowers were collected on the same day, 

 but from patches varying in stage development. 



TABLE VI 



Species 



Trifolium pratense 



Medicago sativa per gm. of 

 flowers 



Buckwheat 10 flowers (aver- 

 age of 4 tests) 



Early in blooming season 



Sugar ia nectar 



Sugar in flowers 



Late in blooming season 



Sugar in nectar Sugar in flowers 



93 



1-5 



1.62 



20.7 



38.9 



0.72 



4.6 



0-3 



I.09 



18.6 

 26.8 



O.60 



more 



synthesis and has greater reserves of food to be secreted by the 



nectaries. 



com- 



mences very rarely before the dehiscence of the anthers; it is 



most 





and it ceases 



as soon as the fruit begins to develop. Bonnier (i) agrees to this 

 proposition and asserts that nectar is simply a manifestation of the 

 surplus of food stored in the nectariferous part corresponding to an 



