YELLOW GROUP 



The plant may be identified by fine, black lines along the 

 stem, also by the violet teeth of the upper lip of corolla, 

 while upon the lower lip there is a black spot near the 

 base. 



Chaff-seed 



Sch<walbea americana. — Family, Figwort. Color, yellowish pur- 

 ple. (See chapter on Purple Flowers, p. 350.) 



Common Bladderwort 



Utricularia 'vulgaris \ — Family, Bladderwort. Color, bright 

 yellow. Leaves, under water, finely cut, bearing little bladders. 

 Summer. 



The bladderworts are insectivorous, aquatic plants. The 

 bladders scattered among the leaves serve two purposes — to 

 float the plant at time of flowering and to entrap minute 

 water-animal food. 



In U. vulgaris the bladders are large. They are furnished 

 with a hinged lid, and with hairs turning inward, so as to 

 prevent the escape of a larva which may have ventured 

 within the mouth of the bladder. It is said that the hairs 

 keep up a wavy motion and so create a sort of current which 

 sucks the creature in if it ventures near these traps. 



The bright yellow blossom, coming to the water's surface 

 on a scape ^ foot long, has a 2 -lipped corolla, like some of the 

 figworts. The leaves are very much dissected, and when 

 first pulled up hang stringily together. Take this unpromis- 

 ing plant home, place it in a basin of water, pick off the 

 mud and slime that cling to it, and you have a beautiful 

 botanical specimen. Slip the pressing-paper under while in 

 the water, and dry with several thicknesses of paper. 



U* subulata is a very small species. A short scape, 3 or 4 inches 

 high, bears yellow blossoms, half a dozen or so, on hair - like 

 pedicels. The leaves are grass-like, not dissected. 



U. inflata. — In this species the otherwise naked flower-stalk 

 bears, about the middle, a whorl of 5 to 9 leaves whose petioles are 

 swollen and bladder-like, tipped with finely dissected leaf-blades, 

 1 to 2 inches long. These are very strange looking leaves, but 

 the swollen petioles, with bladders plentifully interspersed, make 

 the plant float freely and bring the flowers to the top. Lower 

 leaves finely dissected, bearing small bladders. Upper lip of 



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