

ALSINACEAE 423 



styles 3-4, very short : capsules ovoid, surpassing the persistent sepals : seeds about 0.8 mm. 

 broad. 



On river banks, Kentucky and Tennessee. Spring. 



11. CERASTIUM L. 



Annual or perennial, often upright herbs, with pubescent and commonly viscid foliage. 

 Leaves opposite : blades flat. Flowers in forking cymes. Sepals 5, or rarely 4. Petals 

 as many as there are sepals, white, notched or 2-cleft, rarely wanting. Stamens 10 or fewer : 

 filaments shorter than the petals. Ovary 1-celled : styles as many as there are sepals and 

 opposite them, or rarely fewer. Capsule cylindric, often curved, opening by 10 or rarely 

 8 apical tooth-like valves. MOUSE-EAR CHICKWEED. 



Segments of the capsule revolute at maturity. 1. C. Texanum. 



Segments of the capsule erect or spreading. 



Petals shorter than the sepals or about equalling them in length. 



Pedicels shorter than the sepals at maturity. 2. C. viscosum. 



Pedicels longer than the sepals at maturity. 



Leaf-blades less than 4 mm. long : sepals 3-3.5 mm. long : capsules 5-7 



mm. long. 3. C. scmidecandnim. 



Leaf-blades over 4 mm. long : sepals 5-6 mm. long : capsules 7-10 mm. 



long. 4. C. vulgatum. 



Petals manifestly longer than the sepals. 



Annual : foliage viscid : corollas 6-12 mm. broad. 



Pedicels several times longer than the sepals, abruptly bent. 5. C. longipedunculatum. 



Pedicels shorter than the sepals or but slightly longer, straight or 



nearly so. 6. C. brachypodum. 



Perennial : foliage glabrous or pubescent : corollas 17-21 mm. broad. 7. C. arvense. 



1. Cerastium Texanum Britton. Perennial, slender, sparingly pilose. Stem erect, 

 1.5-2 dm. tall, wire-like, forking above : leaf-blades spatulate, 2-4 pairs near the base of 

 the stem, 8-15 mm. long, acute, pilose on both sides : sepals oblong-lanceolate, 4 mm. long, 

 obtuse or notched at the apex : petals white, oblanceolate, delicately nerved, notched at 

 the apex, slightly longer than the sepals : stamens slightly shorter than the petals : capsules 

 5 mm. long, the 10 valves with recurved tips : seeds 0.5 mm. thick, sharply tuberculate, 

 especially on the edges. 



On hills, central Texas and Arizona. 



2. Cerastium viscosum L. Annual, viscid-villous, pale green. Stem branched at 

 the base, the branches erect or decumbent, 1-4 dm. tall, simple below, forking above : leaf- 

 blades varying from spatulate at the base of the stem to oval above, obtuse or rounded at 

 the apex, sessile : pedicels usually shorter than the calyx : sepals oblong-lanceolate, 3-4 

 mm. long, acute : petals white, elliptic-oblong, longer than the sepals, deeply notched, the 

 segments acutish : stamens about | as long as the petals : capsules 7-9 mm. long, the valve- 

 tips ascending : seeds 0.6 mm. broad. 



In meadows and on hillsides. New Brunswick to Ontario, Florida and Texas. Spring. A native 

 of Europe, now widely naturalized. 



3. Cerastium semidecandrum L. Annual or biennial, slender, viscid-villous. 

 Stem simple, or branched at the base, the branches erect or ascending, 0.5-1.5 dm. tall, 

 forking above : leaf-blades oblong, elliptic or obovate, or the lower spatulate, 5-10 cm. 

 long, acute or obtuse, sessile : flowers in open or close cymes : pedicels finally longer than 

 the calyx : sepals lanceolate, 3-3.5 mm. long, acuminate : petals oblong, deeply notched at 

 the apex, about as long as the sepals : stamens often 5 : capsules 5-7 mm. long, slightly 

 curved : seeds 0.5 mm. in diameter. 



In waste places, New Jersey to North Carolina. Naturalized from Europe. Spring. 



4. Cerastium vulgatum L. 'Perennial, slender, pilose and somewhat clammy, dark 

 green. Stem branched at the base, the branches erect or ascending, 1-5 dm. long, with 

 enlarged nodes and spreading or recurved pubescence : leaf-blades oblong, narrowly elliptic 

 or ovate, or the lower spatulate, 0.5-3.5 cm. long, acute or obtuse, ciliate, sessile : cymes 

 at length open : sepals lanceolate, obtuse, ciliate, ascending, 5-6 mm. long, pilose, with 

 scarious margins : petals white, 5-6 mm. long, narrowly obovate, cleft to above the middle : 

 capsules narrowly ovoid, 7-10 mm. long, fluted, the valves lanceolate, spreading : seeds 

 brown, 0.5-1 mm. in diameter. 



Along roadsides and in woods, throughout North America, except the extreme north. Mainly 

 naturalized from Europe. Widely distributed. Spring to fall. 



5. Cerastium longipedunculatum Muhl. Annual or biennial, clammy-villous or 

 glabrate. Stem more or less branched at the base, the branches ascending or reclining, 

 1-5 dm. tall, simple or forked above : leaf-blades thinnish, the lower ones spatulate or ob- 

 lanceolate, 2-8 cm. long, obtuse, the upper stem-leaves oblong, linear-oblong or lanceolate, 



