58 OSMIA AND ITS HABITS 



creatures in his Catalogue of British Hymenop- 

 tera in the British Museum, mentions a case 

 where the bee finding the larger whorls of the 

 shell too wide constructed two cells across the 

 whorl. Another very interesting case given by 

 Smith is of a nest of many cells of the rare Osmia 

 inermis (which in his days was known as Osmia 

 parietina). A slab of stone, 10 inches by 6, was 

 brought to him with 230 cocoons of this Osmia 

 attached to its under side ; when found in the 

 month of November, 1849, about a third of 

 them were empty ; in March of the following 

 year a few males made their appearance and 

 shortly afterwards a few females, and they 

 continued to come out at intervals till the end of 

 June, at which time he had 35 cocoons still 

 unopened ; in 1851 some more emerged, and he 

 opened one or two of the closed ones and found 

 that they still contained living larvae ; he closed 

 them up again, and in April, 1852, examined 

 them and found the larvae still alive ; at the end 

 of May they changed to pupae and appeared as 

 perfect insects, the result being that some of 

 the specimens were at least three years before 

 reaching maturity. 



