Twenty-fifth Annual Meeting. 93 



abundant, and both very pale, with reduced, finely-divided foliage. These two spe- 

 cies are Erysimum parviflorum Nutt. and Lejiidium virginicum L., the former almost 

 leafless in the extreme western counties; the latter very small, many times scarcely 

 four inches high. 



Our common purslane, Portulaca oleracea L. (an introduced species), with its 

 thick, fleshy branches and leaves (a single plant often being over three feet in di- 

 ameter), is replaced in this dry region by the tiny, hairy Portulaca pilosa L., which 

 is less than four inches in diameter. 



In the order Malvacese, or mallow family, we have in eastern Kansas Abutilon 

 avicennte Gaertn, (which, though introduced, is very abundant in our meadows,) also 

 Hibiscus militaris Cav. and Callirrhoe involucrata, all of which are from one to four 

 feet high. These are replaced in the West by a single species, Malvastrum coc- 

 cineum Gr., which is seldom more than six inches high, and has small-lobed, thick, 

 hairy leaves, and grows procumbent instead of upright, as most of the Eastern 

 species. 



The Western Linaceae are Linum sulcatum Ridd. and Linum rigidum Pursh.; 

 the former from 1 foot to li feet tall, very slender, with very few narrow leaves, 

 while the latter is scarcely three inches tall, very bushy and scraggy, and also quite 

 rigid, the leaves being almost subulate. 



The Leguminosie are represented by such plants as Dalea aurea Nutt. and Dalea 

 laxiflora; the first covered with long, silky hairs, and very few small, pinnate leaves; 

 the latter rather tall, but slender, with small leaves, and numerous branches near the 

 top. Also, Psoralea argophylla Ph., and P. tenuiflora Ph., besides several fine-leaved 

 or hairy Astragali. Astragalus bisulcatus Gr., A. pectinatus Dougl., A. flexuosus and 

 A. macrolobus having fine foliage, and Astragalus mollissimus Torr. with rather 

 large leaves, but very hairy. 



Our common evening primroses, of the order Onagraceaj, are entirely replaced by 

 hairy, grayish-colored, narrow-leaved, dwarfed species, most of them less than a foot 

 high, and most of them but three or four inches. The species found in this dry re- 

 gion are: ffinothera triloba Nutt., CEnothera fremontii Watson, CE. hartwegi Benth,, 

 CE. pinnatifida Nutt., and the beautiful little Oenothera canescens Torr., which grows 

 flat on the ground and has such dainty pink, variegated blossoms, as fragrant as vi- 

 olets. In this same order, also, is found Gaura coccinea Nutt., which is very abun- 

 dant in cultivated portions of this dry region. This plant is usually not more than 

 six inches high. 



The most striking example of condensed vegetation is seen in the order Cac- 

 tacese, which is represented in western Kansas by three or four genera. In this order 

 the leaves are reduced to spines, or minute scales, while the thick, fleshy stems con- 

 tain chlorophyll, and the epidermis is furnished with stomata, so that they perform 

 the functions of leaves. Common species of this order are: Oj^untia missouriensis 

 DC, 0. rafinesquii Eng., 0. arborescens, of the prickly-pear family; and Mamillaria 

 vivipara Haw., M. missouriensis DC, and M. dasyacantha, of the ordinary round spe- 

 cies. These vary in size from scarcely an inch in diameter, in some of the Mamil- 

 laria, to 10 or 15 inches in length, in the prickly-pear family. 



The order Compositas is most fully represented in that region, yet most of these 

 are the typical grayish, hairy, narrow-leaved plants peculiar to the Western flora. 



Liatris squarrosa Willd., very common there, is from 6 to 12 inches high, rigid 

 and glabrous, while our L. punctata, and L. spicata Willd., and others common here, 

 are from one to five feet in height, and proportionately larger. 



Aplopappus spinulosus DC, a grayish, scabrous plant, with deeply serrate, lance- 

 olate leaves, is a composite, as common as the sunflower here, though very much 

 smaller, seldom exceeding six inches in height. 



