» 



3 l ° 



BOTANICAL GAZETTE 



[APRIL 



Galium). A characteristic flower is Circaea lutetiana 



tors are: 



Its visi- 







Bees 



Diptera 



JTotal 



Species 



8l.8 

 94 



18. 1 

 5-9 



II 



Individuals 



84 





*" m ¥ 



\ 



Class A is a poor place to look for simple flowers. The majority 

 are social and have epigynous nectaries, both forms of specialization. 

 Except class J?, 1 this class is the only one in w r hich the majority of 

 the species are social. The visits to 23 social A are as follows : bees 

 21.9, Diptera 38.3, other Hymenoptera 27. 3, Lepidoptera 2.6, 

 Coleoptera and Hemiptera 9.6, making a total of 2335. 



Table I, based on 10,041 visits, shows the percentages of visits 

 of all classes to flowers adapted to short-tongued insects, usually 

 small flowers with nectar exposed, partly or wholly concealed, but 

 never deep seated. 



TABLE I 



Bees 



Diptera 



Lepidop- 

 tera 



Coleoptera « Hemiptera 



Lower 



Hymen 



optera 



Percentage of visits 



To non-social flowers 

 To social flowers . . . . 



18. 1 

 41.8 



12.4 



735 



11. 2 

 34-8 



8.6 

 833 



6.1 



787 



4 .1 

 84.9 



Percentage of total visits 



To non-social flowers 

 To social flowers 



59 

 31 



o 



25-3 

 33-^ 



7.2 

 50 



2.0 

 4.4 



0.3 



1.0 



5-3 

 24 -4 



Of the visits of bees, 18 . 1 per cent are to non-social small flowers, 

 and these form 59 . 5 per cent of the total insect visits to such flowers. 

 Sixteen non-social small flowers, on which the individual insects 

 were taken as they came and counted, showed 335 visits and 1520 

 individuals. The percentage of bee visits was 59.1, but of bee 

 individuals 74.2, showing that bees are more important than the 

 percentage of visits indicates. 



