White and Greenish 



Any plant which elects to grow in shallow water must be am- 

 phibious ; it must be able to breathe beneath the surface as the fish 

 do, and also be adapted to thrive without those parts that corre- 

 spond to gills ; for ponds and streams have an unpleasant way of 

 drying up in summer, leaving it stranded on the shore. This ac- 

 counts in part for the variable leaves on the arrow-head, those 

 underneath the water being long and ribbon-like, to bring the 

 greatest possible area into contact with the air with which the 

 water is charged. Broad leaves would be torn to shreds by the 

 current through which grass-like blades glide harmlessly ; but 

 when this plant grows on shore, having no longer use for its lower 

 ribbons, it loses them, and expands only broad arrow-shaped sur- 

 faces to the sunny air, leaves to be supplied with carbonic acid to 

 assimilate, and sunshine to turn off, the oxygen and store up the 

 carbon into their system. 



Water Arum; Marsh Calla 



(Calla palustris) Arum family 



Flowers Minute, greenish yellow, clustered on a cylinder-like, 

 fleshy spadix about I in. long, partly enfolded by a large, 

 white, oval, pointed, erect spathe, the whole resembling a 

 small calla lily open in front. The solitary "flower" on a 

 scape as long as the petioles of leaves, and, like them, sheathed 

 at base. Leaves : Thick, somewhat heart-shaped, their spread- 

 ing or erect petioles 4 to 8 in. long. Fruit: Red berries clus- 

 tered in a head. 



Preferred Habitat Cool Northern bogs ; in or beside sluggish 

 water. 



Flowering Season May June. 



Distribution Nova Scotia southward to Virginia, westward to 

 Minnesota and Iowa. 



At a glance one knows this beautiful denizen of Northern bogs 

 and ditches to be a poor relation of the stately Ethiopian calla lily 

 of our greenhouses. Where the arum grows in rich, cool retreats, 

 it is apt to be abundant, its slender rootstocks running hither and 

 thither through the yielding soil with thrifty rapidity until the place 

 is carpeted with its handsome dark leaves, from which the pure 

 white "flowers" arise ; and yet many flower lovers well up in 

 field practice know it not. Thoreau, for example, was no longer 

 young when he first saw, or, rather, noticed it. " Having found 

 this in one place," he wrote, " 1 now find it in another. Many an 

 object is not seen, though it falls within the range of our visua 

 ray, because it does not come within the range of our intellectual 

 ray. So, in the largest sense, we find only the world we look for. 



'55 



