350 SPIDEEWORT FAMILY. 



J. tenuis. Open loTT grounds and fields, eyerywhere N. : in tufts, with 

 wiry stems 10' -20' high, a loose panicle shorter than the slender leayes near it,- 

 and green flowers with lanceolate very acute sepals longer than the green blunt 

 and scarcely pointed pod. 11 



J. dicbotomus. Low sandy grounds, takes the place of the preceding S. . 

 has more thread-like leaves, flowers move one-sided on the branches of the pan- 

 icle, and greenish sepals only as long as the globular and beak-pointed brown- 

 ish pod. y. 



§ 3. Knottt-leaved Rushes, the stems {often branching abov0) having 2-4 



thread-shaped or laterally flattened leases, which are knotty as if jointed 



{especially when dry) by internal cross-partitions: panicle terminal. Of 



these there are many species, needing close discrimination : the following are 



only the very commonest, especially the northern ones, y. 



J. acumin^tus. Very wet places : 10' -30' high ; heads 3-10 flowered in 



a loose spreading panicle, greenish turning straw-colored or brownish ; sepals 



Jance-awl-shaped, barely as long as the triangular sharp-pointed pod ; stamens 



3 ; seeds merely: acute , at both epds. It flowers in early summer. 



J. noddsus. Mostly in sandy or gi-avdly soil : spreading by slender rool-- 

 stocks which bear little tubek, 6' ^15' high; heads few, crowded, chestnut- 

 brown, each of 8-20 flowers ; sepals lance-linear and awl-pointed, hardly as 

 long as the slender and taper-pointed pod ;' seeds abruptly short-pointed at both 

 ends ; stamens 6. - 



J. soirppides. From New York S. : stems rigid, l°-3'^ high from a 

 thick rootstock ; heads spherical and dense, 1 5 - 80-flowered, dull pale green.; 

 sepals rigid, awl-shaped and bristly-pointed-; stamens 3 ; pod taper-pointed ; seeds 

 abruptly short-pointed at each end. 



J. Canadensis. ' Wet pla«es, common, flowering in autumn, very variable; 

 1'^- 3'^ high; heads mimerous, greenish or light brownish,, 5 -many-flowered; 

 sepals lanceolate, the 3 outer shorter ; stamens 3 ; seeds tail-pointed at both 

 ends. 



. ' . '■ i ■ ■ ■ ' I 



2. IiltZUIiA, WOOD-RUSH. (LMc/o/a is Italian for the jfow-wjorm.) y 



Ii. pilbsa. Shady banks N. :_ 6' -9' high; with lance-lineai- leaves, and 

 chestnut-brown flowers in an umbel, in spring. 



L. campdstris. Dry or moist fields and woods, 6' -12' high, with linear 

 leaves, and 4-12 spikes or short heads of light brown or straw-colored heads in 

 an umbel, in spring. 



126. C0MMELYNACE.ffi3, SPIDERWORT FAMILY, 



Herbs with muc;ilaginous juice, jointed and mostly branching leafy 

 stems, and perfect flowers, having a perianth of usually 3 green and 

 persistent sepals, and three ephemeral petals (these commonly melt 

 into jelly the night after expansion) ; 6 stamens, some of them often 

 imperfect, and a free 2 -3-oelled ovary ; style and stigma one. Pod 

 2 - 3-celled, few-seeded. Not aquatic, the greater part tropical. 



1. OOMMELYNA. Flowers blue, in-egular. Sepals unequal, 2 of them sometimes 



imited by their contiguous margins. Two of the petals rounded and on slen- 

 der claws, the odd one smaller or abortive. Stamens unequal ; tliree of them 

 fertile, one of these bent inw,ards; thi'ee smaller and with cross-shaped im- 

 perfect anthers : filaments naked. Leaves abruptly contracted and sheathing 

 at base, the uppermnst fonning a spathe for the flOAvers. 



2. TRADESCANTIA. Flowers regular. Petals all alike, ovate, sessile. The 



6 stamens all with similar and good anthers, on bearded filaments. 



1. COMMEL'i'N'A, DAY-FLOWER. (There were three Commdyns, 

 Dutch botanists, two of them were authors, the other published nothing. In 

 naming this genus for them, Linnaeus is understood to have designated the 



