Habit 



The status — native or introduced — refers to the region or 

 regions covered by the particular part of the checkUst: the 

 49 continental United States and Canada, Hawaii, or the 

 Caribbean region. If the status is unknown, an asterisk 

 appears instead of "N" or "I." A blank space in the first 

 position of the Habit column indicates a species of which 

 only varieties other than the type variety have grown spon- 

 taneously in the United States. Combinations of codes such 

 as AP, ST, or ZE indicate a variable growth cycle, habit, 

 or special habitat. 



Distribution 



Regions are identified on the map on the facing page. Region 

 V (Virgin Islands other than U.S. Virgin Islands) is cited 

 only for plants that do not occur in Region C (Puerto Rico 

 and U.S. Virgin Islands). For some plants, we have replaced 

 certain region numbers with "I," indicating that, in those 

 regions but not in the other regions, the plants have been 

 introduced and subsequently have grown there spontaneously 

 or with "E," if the plants are extinct except in cultivation. 



Family Name/No. 



Family names follow the system used by the United States 

 National Herbarium, Smithsonian Institution, Washington, 

 D.C. 



