IMPATIENS FULVA.- 



■SPOTTED TUUCII-ME-NOT, OR SNAP-WEED. 43 



The genus has been the victim of uncertainties in some of its 

 relationships, and the species have fared no better. LinUceus, 

 who arranged plants on his sexual system, classed Inipatiens as a 

 syngenesious plant! In this class were also included what we 

 now call composites. Nuttall, who also arranged his plants on 

 the sexual system, places it in the class Pentandria. Nor has it 

 been more settled under the natural system of more modern 

 botanists. Wood, from whom w^e quote, gives it to the order 

 BalsaminacecE. But many modern botanists do not regard this 

 as an independent order, and the student from this point of view 

 would have to search for our plant among the Geraniacece. 



A peculiar feature of this and allied species of Impatiens is 

 that the later flowers are often cleistogenous ; that is to say, 

 while the earlier flowers have petals and are complete in all their 

 parts, as in our plate, the later ones have no petals, or anything 

 that would be popularly called a flower, and yield barely pollen 

 enough to fertilize the ovary and produce seed. Fertilization 

 is effected before the bud opens, and the first knowledge the 

 observer has of the existence of any flowering operation is by 

 the growing seed vessel pushing from the bud. In England, 

 where close observadons on this species have been made by Mr. 

 A. W. Bennet, these cleistogenenic flowers have been found in 

 the proportion of twenty to one of the petal bearing, or as they 

 are called, "perfect" ones. In the vicinity of the writer's home 

 the propordon is generally about one-half. In Europe the per- 

 fect flowers seem rarely to produce seeds. But here they bear 

 freely, and plants may be seen covered with seed vessels before 

 any cleistogene flowers appear. The subject is one of great 

 interest, and will prove an inviting field for the student fond of 

 original research. 



There are many facts worth noting in the life-history of the 

 Impatiens fitlva. In the " Bulledn of the Torrey Bot. Club" for 

 1872, it is noted that the inhabitants of Green county, New York, 

 call it " Silver leaf," because when placed under water the leaf 

 glistens like silver, and does not get wet. In the volume for 



