350 SPIDERWORT FAMILY. 



J. t6nuis. Open low grounds and fields, everywhere N. : in tufts, with 

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

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

 and scarcely pointed pod. 2/ 



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

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

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

 ish pod. ~)l 



3. KNOTTY-LEAVED RUSHES, the stems (often branching above) having 2-4 

 thread-shiiped or laterally flattened leaves, 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. ^ 



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

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

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

 3 ; seeds merely.acute at both ends. It flowers in early summer. 



J. nodosus. Mostly in sandy or gravelly soil : spreading by slender root- 

 stocks which bear little tubers, 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. SCirpoides. 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 places, common, flowering in autumn, very variable, 

 l-3 high; heads numerous, greenish or light brownish, 5 - many-flowered ; 

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

 ends. 



2. LTJZTJL A, WOOD-RUSH. (Lucfola. is Italian for the glow-worm.) % 

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



chestnut-brown flowers in an umbel, in spring. 



L. campestris. 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. COMMELYNACE^E, SPIDERWORT FAMILY. 



Herbs with mucilaginous 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-celled ovary ; style and stigma one. Pod 

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



1. COMMELYNA. Flowers blue, irregular. Sepals unequal, 2 of them sometimes 



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

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

 fertile, one of these bent inwards; three smaller and with cross-shaped im- 

 perfect anthers : filaments naked. Leaves abruptly contracted and sheathing 

 at base, the uppermost forming a spathe for the flowers. 



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



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



1. COMMELlTNA, DAY-FLOWER. (There were three Commelyns, 

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

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



