68 FLO WERS OF FIELD, HILL, AND SWAMP 



enclosed horns, and see what strange things the stamens are. 

 The little fringed lip at the tip is not the anther. A tube of an- 

 thers below, united, stands around the pistil. Their long cells 

 open lengthwise, often in bud. The pollen, instead of being in 

 grains, is in a long, yellow, flat mass, one in each cell (in shape 

 like an apple seed), which can be squeezed out entire with thumb 

 and finger. Two of these, from different, adjacent anthers, cling 

 together by a thread, and adhere to insects visiting them, and so 

 are carried to other flowers. 



There are seemingly two pistils (really two ovaries) united above 

 into a large, flattish, sticky stigma, which catches and holds the 

 pollen-masses borne to it by bees. In a flower the pollen-masses 

 lie too low for its own stigma. The insect visit is absolutely 

 necessary for fertilization. Now perhaps we have found a use 

 for the hoods. They probably collect and store honey, and so 

 invite the insects, upon whose help the flower is dependent. The 

 reflexed corolla could not hold any nectar, and without honey 

 bees would pass the milkweed by. 



The swamp-milkweed is well known. It is smooth-stemmed, 

 very leafy, with but little milky juice. 2 to 3 feet high. 



67, Hedge-hyssop 



Gratlola Virginihna. — Family, Figwort. Color, yellowish- 

 white. Leaves, oppo.site, sessile, long, narrow, acute at both 

 ends. Time, summer. 



Low, light-green plants, in wet, .sandy soil. Flowers with a 

 darker-yellowish tube, and lighter, nearly white, lobes. Two-lipped 

 corolla, the lower lip 3-cleft, the other 2. There are only 2 fer-' 

 tile stamens. The stems often lie upon the ground, branched, 

 with flowers prominent on long peduncles. 



68. Golden Hedge-hyssop 



G. aUrea is a deep yellow species, very common along the 

 seashore in wet sand. 



69. False Pimpernel 

 llysanthes ripdria. — Family, Figwort. Color, light purple. 



