<Tr> <Td_colspan="2"> <P>> 300 species, including </P> <Ul> <Li> Osmia atriventris </Li> <Li> Osmia avosetta </Li> <Li> Osmia bicolor </Li> <Li> Osmia bicornis </Li> <Li> Osmia caerulescens </Li> <Li> Osmia californica </Li> <Li> Osmia cornifrons </Li> <Li> Osmia cornuta </Li> <Li> Osmia inermis </Li> <Li> Osmia latreillei </Li> <Li> Osmia lignaria </Li> <Li> Osmia ribifloris </Li> <Li> Osmia uncinata </Li> <Li> Osmia xanthomelana </Li> </Ul> </Td> </Tr> <P>> 300 species, including </P> <Ul> <Li> Osmia atriventris </Li> <Li> Osmia avosetta </Li> <Li> Osmia bicolor </Li> <Li> Osmia bicornis </Li> <Li> Osmia caerulescens </Li> <Li> Osmia californica </Li> <Li> Osmia cornifrons </Li> <Li> Osmia cornuta </Li> <Li> Osmia inermis </Li> <Li> Osmia latreillei </Li> <Li> Osmia lignaria </Li> <Li> Osmia ribifloris </Li> <Li> Osmia uncinata </Li> <Li> Osmia xanthomelana </Li> </Ul> <P> Mason bee is a name now commonly used for species of bees in the genus Osmia, of the family Megachilidae . Mason bees are named for their habit of using mud or other "masonry" products in constructing their nests, which are made in naturally occurring gaps such as between cracks in stones or other small dark cavities; when available some species preferentially use hollow stems or holes in wood made by wood - boring insects . </P>

Where are mason bees found in the us