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TEXTBOOK OF BOTANY 



food supply is secured from the host. The plants are often evergreen 

 and may be found on elms, poplars, oaks, mesquite, pines, larches, and 

 many other genera. A few bear scales without chlorophyll, and hence 

 are strictly parasitic. The mistletoes are of little commercial value except 

 as curiosities and as the cause of sUght damage to the host plant (Fig. 

 343). 



Fig. 343. A branch of mistletoe (Phoradendion) with fruit. 



The crowfoot family (Ranunculaceae) . The buttercups, anemone, 

 peony, larkspur, and columbine are plants of the crowfoot family. They 

 are nearly all herbs and generally perennial. These plants are not of 

 great economic importance, being desired by man chiefly for their 

 flowers. Cattle are poisoned by larkspur; a few useful drugs, such as 

 aconite and cimicifuga, are obtained from some species. There are 

 about 30 genera and 1200 species. 



The mustard family {Brassicaceae or Cruciferae). The plants of this 

 important family are widely distributed in temperate climates. Here 

 belong the cultivated cabbage, cauliflower, turnip, radish, and cress; 

 the ornamental wallflowers, candytuft, and stocks; and numerous com- 

 mon weeds, such as wild mustard, shepherd's purse, pepper grass. The 

 cultivated species and weeds are of old-world origin. 



The mustards are generally recognized by the arrangement of the 

 four petals into a Maltese cross, the pungent taste, and the four long 

 and two short stamens. From a simple, small, rosette-like ancestor the 

 common cabbage, broccoli, kale, kohlrabi, brussels sprouts, and cauli- 



