Chapter XXXI. 



From Geraniums to Maples and Touch-me-nots. 



if 



The nineteenth order includes the geraniums, the wood- 

 sorrels, the nasturtium vines, the flaxes, the rues and prickly 

 ashes, the polygalas, the spurges, castor-beans, and tapiocas, the 

 water-starworts and several families not represented in North 

 America. A variety of interesting plants in this order are 

 cultivated, or are employed for various economic purposes. 

 For example, the coca tree, from which the well-known anes- 

 thetic, cocaine, is manufactured, should be grouped here; also 

 the oranges, limes and lemons, and the ailanthus tree, introduced 

 from China. To the spurge family, too, of this order, there 

 belong a number of singular cactus-like plants most abundant 

 in South Africa. Several of the families are represented in 

 Minnesota, but most of them by only a few species. 



Geraniums. Four varieties of geranium occur wild in Min- 

 nesota. These all have regular flax-like flowers and slender 

 capsules which open by five clefts running lengthwise of the 

 pod. A peculiarity of the geranium pod is that, when it opens, 

 it does so suddenly, splitting from the base upward. Five 

 pieces, each carrying a seed at its lower end, split off in this 

 manner from a central column and the seeds are projected some 

 distance into the air as if thrown from a catapult. The differ- 

 ent kinds of wild geraniums may be distinguished by their 

 leaves. The common spotted-leafed geranium has rose-colored 

 flowers and leaves palmately divided and spotted. The red- 

 robin has much smaller leaves without the conspicuous spots. 

 The Carolina geranium has its leaves cut up into finer seg- 

 ments than the others and the flowers are of a pale, whitish hue. 



Wood-sorrels. The wood-sorrels are well-known for their 

 three-leafleted leaves, not unlike those of the white clover, but 

 with a distinct acid taste. There are at least three varieties 



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