OP THE VALISXERIA. 335 



the above account highly probable in a coun- 

 try where the sun has so much more power, 

 even if it did nut comu iVom the most faith- 

 ful and philosophical botanist of antiquity, 

 and I have always w ith confidence cited it on 

 his authority. Tlie reader, however, will per- 

 ceive that the only imj)ortant circumstance 

 for our purpose is the closing of the flowers 

 at night, which is sufliciently well established. 

 But the most memorable of acpiatic plants 

 is the Valhueria spiralis, well figured and 

 described by Micheli, A'w. Gen. t. 10, which 

 grows ut the bottoms of ditches in Italy. In 

 this the fertile flowers stand on long spiral 

 stalks, and these by uncoiling elevate them 

 to the surface of the water, where the calyx 

 expands in the open air. In the mean while 

 plenty of barren flowsors are produced on a 

 distinct root, on short straight stalks, from 

 which they rise like little separate white bub- 

 bles, suddenly expanding when they reach 

 the surface, and floating about in such abun- 

 dance as to cover it entirely. Thus their pol- 

 len is scattered over the stigmas of the first- 

 mentioned blossoms, whose stalks soon after- 

 wards resume their spiral figure, and the 



