MIMOSA 49 



earlier botanists, and it has been the object 

 of a succession of investigations for more 

 than a century. The plant has become a 

 classical illustration in botanical literature, 

 and a drawing showing positions taken by 

 the leaves after movement, made by Duchar- 

 tre many years ago, is still reproduced in text 

 books. 



The equatorial zone is the home of an enor- 

 mous number of species. The island of Ja- 

 maica, with an area of about 6,000 square 

 miles, about that of Connecticut, furnishes 

 approximately four-fifths as many species of 

 flowering plants as are to be found in the 

 United States east of the Mississippi river. 

 The advent of modern man into the teeming 

 tropical areas, and the facilities he afforded 

 intentionally and unintentionally for distri- 

 bution has led to a wholesale emigration and 

 intermingling of tropical forms. 



Mimosa pudica was originally an inhabi- 

 tant of the plains of Brazil and Venezuela, but 

 it has accompanied man in his journeys 

 around the world in the equatorial regions. 

 It has become a virile pest in fields, gardens 

 and pastures in warm countries, and is culti- 

 vated in greenhouses in latitudes as high as 

 55° N. 



It is a low, spreading, prostrate, woody 

 plant in the tropics. The forms seen in north- 



