82 PHYSICAL GEOGRAPHY. 



nine belong to this genus. They are rarer than in former years, 

 G. crinita, or fringed gentian, being now rarely found. One 

 species, with a short stem, is a very late bloomer in autumn. It is 

 of a very deep blue color, and appears after the first frosts. 



The Milkweed Family is particularly rich in species of the 

 genus Asclepias, of which there are fourteen different forms. 

 Asclepia verticillata, with its greenish-white flowers, is rapidly, 

 for some reason, increasing in southern Nebraska. 



The Buckwheat Family is represented by forty-two species. 

 The joint-weeds (Polygonum) are the most abundant. Of these 

 there are nineteen species and varieties. Polygonum amphibium 

 and its two varieties, are the most abundant, it being found abund- 

 antly in low, swampy ground. The Missouri bottoms seem to be 

 its centre of distribution. The plant is remarkable for the large 

 amount of tannic acid which it contains. 



The Spurge Family is conspicuous in the State, not for the 

 number of species, as there are only twenty-two, but because of 

 the singular appearance of a few forms. Euphorbia marginata, 

 so abundant in every county, is conspicuous for its beautiful silver- 

 white margined leaves. These are recognized a great way off. 

 This plant is cultivated in the east for its beauty of form. Here, 

 in places, its very abundance makes it a nuisance. E. hete7'o- 

 phylla, on the other hand, has a beautiful scarlet-red base to its 

 upper leaves. This species does not make itself so conspicuous as 

 the last, as it needs to be sought after to be found. 



The Orchis Family is well represented by twenty-nine species. 

 Only a few are abundant. The Great Western White Orchis 

 (Haberiiaria leucophced) is found sparingly in all low lands. Its 

 cream-white raceme of flowers are remarkable alike for their 

 beauty and their delicious odor. The common Lady Slippers 

 (Cypr/pedium) are abundant in some woodlands. C. pubescens is 

 most frequently met with, and grows to a size rarely observed in 

 the east. 



The Iris Family is chiefly remarkable for the great number of 

 individuals^ of one species, namely, the Blue-Eyed Grass (Sisyn-in- 

 chium Bermudiand). When in bloom, it is observed everywhere 

 on the prairies, because of the attractiveness of its numerous, tiny, 

 star-like, blue and white flowers. 



The Lily Family furnishes one of the earliest of our flowering 

 plants, namely, the DogVTooth Violets (Erythrofiium). E. 



