. 



^"*?. k ' 



27. A solitary bee (Anthophora 

 acervorum) on a flower. 



29. Osmia rufa. Larvae feeding 

 on pollen masses in their mud 

 cells. 



28. The solitary mason bee 

 (Osmia rufa), male above, 

 female below. 



30. Osmia rufa. View of a 

 many-celled nest built behind a 

 door lock. 



