ALSINACEAE 421 



9. Alslnopsls Carollnlana (Walt. ) 'Small. Perenni{il, tufted, slender. Stems nmcli 

 branched at tlie base, the branches ascending or decumbent, 0.5-3 dm. tall, very leafy below, 

 glandular, often viscid and nearly naked above, the scape-like portion sparingly forking near 

 the top : leaves firm ; blades linear-subulate, 0.5-1 cm. long, acute, channeled above, ses- 

 sile, imbricated on the lower part of the branches : cymes few-flowered : pedicels slender, 

 1-5 cm. long : sepals ovate, 2.5 mm. long, ol)tuse : petals oblanceolate, about thrice as long 

 as the sepals, rounded at the apex : capsules ovoid, nearly twice as long as the sepals: seeds 

 0.5 mm. broad. [Arenaria squarrosa Michx.] 



On sand hills and in pine lands, Xew York to Florida. Spring and summer. 



9. A REN ARIA L. 



Annual or perennial herbs, sometimes woody at the base, with more or less diffusely 

 branched stems. Leaves opposite, sometimes clustered, withotit stipules : blades flattened 

 or merely subulate or filiform. Flowers in open or capitate cymes or solitary in the 

 axils. Sepals 5, often ribbed. Petals 5, white, entire or rarely notched, occasionally 

 wanting. Stamens normally 10 : filaments slender. Ovary 1 -celled : styles 3, or rarely 

 2-5. Capsule globose to oblong, opening by twice as many tooth-like valves as there are 

 styles. Seeds numerous, sometimes flattened. Sandwort. 



Plants annual. 



Sepals pubescent : pedicels less than 13 mm. long. 1. A. xerpyllifolia. 



Sepals glabrous : pedicels over 13 mm. long. 2. A. BcnihamU. 



Plants perennial. 3. .1. lanuginosa. 



1. Arenaria serpyllifolia L. Annual, slender, puberulent and roughish, bright 

 green. Stem diffusely l)rauched, the Inanches spreading, 1-4 dm. long, at length wire- 

 like : leaf-blades ovate or ljrt)adly elliptic, 2-6 mm. long, short-acuminate, with very 

 minute spine-like cilia, narrowed at the base, sessile or mainly so : sepals 5, lanceolate, 

 3-4 mm. long, acuminate, witli broad hyaline margins and spine-like hairs on the back : 

 petals oblong-ovate, 2 mm. long, obtuse, white, shorter than the sepals, clawed : anthers 

 lilac : ca[)sules conic, 2.5-4 mm. long, yellowish green, slightly constricted above the 

 middle, the valves lanceolate. 



In dry soil or waste places, throughout North America, except northern British America. Nat- 

 uralized from Europe. Native also of Asia. Spring. 



2. Arenaria Benthamii Fenzl. Annual, slender, bright green. Stems more or less 

 branched at the base, the branches wire-like, erect or ascending, 0.5-1.5 dm. tall, forking, 

 pubescent in lines : leaf-blades thickish, the lower ones spatulate or elliptic-spatulate, 

 petioled, the upper ones oblong or elliptic, sessile, all acute, sparingly ciliate : pedicels 

 filiform, 1.5-3 cm. long : sepals ovate, 2.5 mm. long, acutish : petals elliptic, nearly as 

 long as the sepals, slightly acuminate at the apex : capsules ovoid, about 3 mm. long, 

 acutish : seeds reniform, about 0.6 mm. broad, minutely tuberculate. 



On rocky hillsides, Texas. Spring. 



3. Arenaria lanuginosa (Michx.) Rohrb. Perennial, slender, light green. Stems 

 branched at the base, the branches spreading, prostrate, 3-13 dm. long, forking, more or less 

 pubescent with hooked hairs : leaf-blades narrowly elliptic or linear-spatula te, 1-2 cm. 

 long, acute, sessile or short-petioled : pedicels filiform, 1.5-4 cm. long: sepals lanceolate, 

 2.5-3.5 mm. long, acute : petals 1-5, shorter than the sepals or none : capsules ovoid, about 

 as long as the sepals : seeds 0.8 mm. long, shining. [^Arenaria diffusa Ell.] 



In shaded situations, North Carolina to Texas and Florida. Spring to fall. 



10. ALSINE L. 



Annual or perennial herbs, with weak spi'eading stems. Leaves opposite : blades nar- 

 row or dilated. Flowers in more or less open cymes. Sepals 5 or 4, not ribbed. Petals 

 5 or 4, white, 2-cleft or 2-parted, rarely wanting. Stamens 10 or fewer, hypogynous : fila- 

 ments slender. Ovary 1 -celled : styles 3 or 4, or rarely 5, usually opposite the sepals. 

 Capsule relatively short, opening by twice as many valves as there are styles. Seeds flat- 

 tened or globose. [Sfell((rinlj.'\ Chickweed. Starwort. Stitchwort. 



Styles 5. 1. ,-1. aquatica. 



Styles 3 or rarely -1. 

 A. Corolla present. 



a. Leaf- blades manifestly petioled. 

 Petals shorter than the sepals : sepals mostly over 3 mm. long. 2. A. media. 



Petals longer than the sepals : sepals mostly less than 3 mm. long. 3. --1. Bahlwinii. 



