Yellow and Orange 



clothing of man or beast passing tlieir way, in the hope of 

 dropping off in a suitable place to found another colony. 



Sensitive Pea; Wild or Small-flowered Sen- 

 sitive Plant 



{Cassia nictitans) Senna family 



Flowers — Yellow, regular, 5-parted, about % in. across ; 2 or 5 

 together in the axils. Stem: Weak, 6 to 15 in. tall, branch- 

 ing, leafy. Leaves: Alternate, sensitive, compounded of 12 

 to 44 small, narrowly oblong leaflets ; a cup-shaped gland 

 below lowest pair; stipules persistent. Fruit: A pod, an 

 inch long or more, containing numerous seeds. 



Preferred Habitat— Dry fields, sandy wasteland, roadsides. 



Flowering Season — July — October. 



Distribution — New England westward to Indiana, south to Georgia 

 and Texas. 



How many of us ever pause to test the sensitiveness of this 

 exquisite foliage that borders the roadsides, and in appearance is 

 almost identical with the South American sensitive plant's, so 

 commonly cultivated in hothouses here ? Failing to see its fine 

 little leaflets fold together instantly when brushed with the hand, 

 as they do in the tropical species {Mimosa pudica), many pass on, 

 concluding its title a misnomer. By simply touching the leaves, 

 however roughly, only a tardy and slight movement follows. A 

 sharp blow produces quicker effect, while if the whole plant be 

 shaken by forcibly snapping the stem with the finger, all the 

 leaves will be strongly affected ; their sensitiveness being appar- 

 ently more aroused by vibration through jarring than by contact 

 with foreign bodies. The leaves, which ordinarily spread out 

 flat, partly close in bright sunshine and "go to sleep" at night, 

 not to expose their sensitive upper surfaces to fierce heat in the 

 first case, and to cold by radiation in the second. "Lifeless 

 things may be moved or acted on," says Asa Gray; "living 

 beings move and act— plants less conspicuously, but no less 

 really than animals. In sharing the mysterious gift of life they 

 share some of its simpler powers." 



The Partridge Pea or Large-flowered Sensitive Plant (C. 

 Chamaecrista) likewise goes to sleep; the ten to fifteen pairs of 

 leaflets which, with a terminal one, make up each pinnate leaf, 

 slowly turning their outer edges uppermost after sunset, and over- 

 lapping as they flatten themselves against their common stem 

 until the entire aspect of the plant is changed. By day the ex- 

 panded foliage is feathery, fine, acacia-like ; at night the bushy, 



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