COLORS OF NORTH AMERICAN FLOWERS 



of families, as the mustard and saxifrage families. The pur- 

 ple trillium and Dutchman's-pipe have brown or lurid-purple 

 hues. The custard-apple (Asinima triloba) is at first greenish 

 yellow, changing to dull purple. In most instances the brown 

 colors of flowers are due to a mixture of chlorophyll or carrotin 

 with anthocyanin. Among the brown flowers containing two 

 pigments are Carolina allspice {C ahjcanthus) , the gooseberry, 

 wild ginger {Asarum), Adonis vernalis, and various orchids. 

 The black spots on the wings, or alse, of the bean {Vicia Faba) 

 contain an ohve-brown pigment dissolved in the cell-sap. 

 The spots appear black because of the flat epidermal cells. 

 (Fig. 101.) 



THE COLORS OF NORTHERN APETALOUS FLOWERS 



257 



