CLASSIFICATION OF ANGIOSPERMS. 



395 



The so-called Insect Flowers {Pyrcthri Flores) are the 

 partly expanded flower-heads of several species of Chrysanthe- 

 mum, and are used in the preparation of a powder which is a 

 powerful insecticide. The plants are perennial herbs resembling 



Fig. i8ia. Daisy-fleabane (Erigeron annuus). 



in their habits the common white daisy (C Leucanthemuin) . The 

 Dalmatian Insect Flowers are obtained from C. cinerariifoUiun, 

 growing in Dalmatia, and cultivated in Northern Africa, Cali- 

 fornia and New York. The heads as they occur in the market 

 are about 12 mm. broad, light yellowish-brown and have a slightly 



