350 SPIDEETTOET FAMILY. 



J. tenuis. Open low grounds and fields, everjrwhere 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 sfarcely pointed pod. y. 



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. y, 



§ 3. Knottt-lbaved Rushes, the stems (often branching above) having 2-4 

 thread-shaped 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. 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 

 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. nod6su.S. Mostly in sandy or gravelly soil : spreading by slender root- 

 stocks which bear little tubers, 6' - 1 5' 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. scirpoldes. From New York S. : stems rigid, l°-3o high from a 

 thick rootstock ; heads spherical and dense, 15-80-flowered, dull pale green; 

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

 abruptly short-pointed at each end. 



J. Canadensis. Wet plaoes, 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. LUZUIiA, WOOD-RUSH. (Luciola is Italian {or the glow-worm.) y 



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

 chestnut-brown flowers in an umbel, in spring. 



L. camp^Stris. 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^, SPIDEEWORT 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. TEADESCANTIA. Flowers regular. Petals all alike, ovate, sessUe. The 



6 stamens aU with similar and good anthers, on bearded fflaments. 



1. COMMELYINA, DAY-FLOWER. (There were three Commdyns, 

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

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



