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{Lobelia syphilitica), blue. It is true that these flowers do not 

 always occur in the same place, yet in some cases they are 

 adapted to the same general class of visitors and it must be 

 of some advantage to have a contrast in colors. It is note- 

 worthy also that some species under different conditions show 

 changes in the color of flowers. Kerner von Marilaun cites 

 a species of Campanula {C. trachelium) which has white flow- 

 ers in the neigliborhood of Brenners, Austria, but in the val- 

 leys of the limestone Alps the flowers are blue The alpine 

 flora &f the Rocky Mountains is remarkable in showing 

 changes in the colors of flowers from one altitude to another. 

 The genus Delphinium is remarkable in showiug color 

 variations. A large larkspur, common everywhere in Iowa, 

 is described as having blue flowers, but the form commonly 

 found at Ames, Iowa, and LaOrosse, Wisconsin, is whitish 

 with occasionally a slight tinge of blue. Another species, D. 

 tricorne, which occurs in southern Iowa usually has blue flow- 

 ers, but on the limestone cliffs at Giencoe, Missouri, only 

 white flowers occur. I was therefore agreeably surprised to 

 find that in the great American bottom opposite St. Louis 

 near Falling Springs, in deep rich woods a beautiful pink 

 form occurred. Our painted cup [Castilleia coccinea) usually 

 has red flowers, but at Madison, Wisconsin, where I noticed 

 the plant for several years in a swamp, the yellow flowered 

 form occurred. Mr. Uphara, however, states that some 

 years upon districts ten to twenty miles in extent the flowers 

 are all yellow, elsewhere scarlet with occasional yellow flow- 

 ers intermixed. Fritz Mueller has observed that some plants 

 do not flower continuously, but concentrate their efforts to 

 certain days. A species of Cyphella (one of the Iridaceae) 

 was observed in Itajahy, Brazil, to flower in profusion along 

 the roads for miles, but the following day it was not observed. 



