





1917] KENOYER— NECTAR SECRETION 201 



Other flowers analyzed , among them being Antirrhinum majus, 

 Cucumis sativus, Salvia splendens, and Coleus Blumei, contain less 

 sugar and secrete less sugar when kept in the dark; furthermore, 

 the nectar is usually less in volume. Euphorbia pule her rima does 

 not begin secretion in a dark chamber, and Abutilon striatum 

 secretes only very slowly and very scantily. Even plum branches, 

 which contain supplies of stored food, when developed in the dark 

 have little more than half as much sugar in the tissues and about 

 one-fourth as much nectar as when developed in the light. 



FERTILITY OF SOIL AND VIGOR OF PLANT 



Hunter (ii) states that alfalfa yields the greatest amount of 

 nectar under conditions that tend to give it the most vigorous 

 growth, proper heat, and moisture upon suitable soil. All of my 

 observations and experiments tend to confirm this for the various 

 plants investigated. Red clovers grown on fertilized plots were 



found to contain slightly more sugar and to secrete slightly more as 

 nectar than those on the unfertilized control plots adjoining. 



Bonnier (2) has experimented on the secretion of several plants 

 as influenced by different soils. He finds that Sinapis alba, Isatis 

 tinctoria, and Medic ago sativa yield most nectar on limy soil, while 

 Phacelia tanacetifolia does better on clay and Fagopyrum esculentum 

 on sand. It is probable that soils which are conducive to greater 

 vigor and more surplus food in the plant are on the whole more 

 favorable for nectar yield. 



White clover, the leading honey plant of this section, collected 

 the same day in the same part of the city gives the tests shown in 

 table V. 



TABLE V 



Condition 



Sugar per gm. of flowers is 



Nectar Flowers 



Stunted by rank growth of weeds. . . 



Stunted by close mowing 



Vigorous 



Vigorous plants of buckwheat yield about twice as much nectar 

 as do weak ones in the same bed. The flowers are found on analysis 



