Fig. 220. — Life-histories of Insects. 



L., P., and .4., larva, pupa, and adult respectively of water-beetle (Dytisciis 

 marginalis) ; /., p., a., larva, pupa, and adult of blue-bottle fly {Musca 

 vomitoria): I A, pA, a.i, larva, pupa, and adult of Cossus ligniperda. 



