24 



THE AMERICAN NATURALIST [Vol. XLII 



when ripening. It there branches freely, assuming the 

 form of a large complex blanched rootstock, and becomes 

 wholly parasitic. It passes its whole mature life under 

 ground except that some of its branches rise above ground 

 to flower, but those branches always die when the fruit 

 has ripened. Its earlier parasitism is by sessile haus- 

 toria, which are soon discarded, and its later parasitism 

 is by haustoria-tipped tendrils, sometimes erroneously 



railed roots or rootlets, which issue from the under- 

 ground stem and branches. No chlorophyl is produced 

 and no functional foliage or functional roots are devel- 

 oped after the plant begins its burrowing. Example: 

 Lathrcea squamaria. This group has no known American 

 representatives. 



