^8 THE PLANT WORLD. 



dantly in our fields. Thus the sorghum of commerce belongs to the 

 same genus as the dreaded "Johnson-grass" of the South {^Sorghum 

 halepense), one of the worst usurpers of cultivated lands. 



The Sedges ( Cyperacecs) also form a large family, with 65 genera 

 and 3,000 species; more than a third of the species, however, are com- 

 prised in the single genus Carex. Like the grasses, the inflorescence 

 is in spikes or panicles, made up of small spikelets; but when we come 

 to examine the scales we shall find that there is no palet, i. e , the 

 flower-bearing scale is single instead of double. Moreover, there is 

 nearly always to be found some trace of a floral envelope, in the shape 

 of small bristles. The leaves are sometimes grass-like, sometimes 

 slender and wiry, but never exhibit ligules at their bases. The stem 

 is almost invariably solid. 



These plants, as has been intimated, grow intermixed with grass 

 in various situations, the majority of the species, however, where the 

 soil is somewhat moist. In certain sections of the country where the 

 native grasses are few and scanty, various sedges are of value for for- 

 age purposes, but the seeds, not being rich in starch, are not used for 

 food. 



The Rushes or Bulrushes {/uncacecE ) take us several steps higher 

 in the ascending scale of plant development. These plants have a dis- 

 tinct floral envelope or perianth, of six parts, but the texture is dry 

 and chaffy, like the scales of the last two families. The ovary differs 

 from that of the grasses and sedges in being three-celled instead of 

 one-celled, so that the seeds are several instead of one in each seed- 

 pod. The family contains only seven genera with about 200 species; 

 the typical genus, Juncus, embraces three-fourths of these. The 

 plants have little economic value ; in Holland they are used as winter 

 coverings for the newly planted bed of hyacinths and tulips ; in this we 

 have a peculiar coincidence, for the Juncacese are generally believed 

 to be reduced members of the original great Lily family, of which the 

 hyacinth and tulip are conspicuous examples. This group, with its 

 allies, will form the subject of next month's paper. 



Dr. Charles Mohr of Mobile, Alabama, is now at the National 

 Herbarium in Washington, finishing the manuscript for his Catalogue 

 of Alabama Plants. It is to be published as a contribution from the 

 National Herbarium, and will contain descriptions of the new, rare or 

 otherwise interesting species found in the State. 



Prof. O. F. Cook has returned from his expedition of last winter 

 to Liberia, bringing with him to the U. S. National Museum a val- 

 uable collection of plants. He has consented to contribute to an early 

 issue of The Plant World an article on African botanizing. 



