84 American Midland Naturalist Monograph No. 7 



2. Stellaria L. — Chickweed 

 {Alsine L. ex p., non Wahl.) 

 1. Leaves oval or ovate. 



2. Petals longer than the sepals; plants perennial. 



3. Stems glandular-pnberulent above, glabrous below; leaves 

 ovate; styles 5; waste places, occasional; adv. from Eur. 



Water Chickweed S. aquatica (L.) Scop. 



3. Stems with two lines of hairs; leaves elliptical; styles 3; 

 wooded slopes and ra\ines, rare; Cook and Du Page coun- 

 ties. June-July .S". pubcra Michx. 



2. Petals shorter than the sepals; stem terete, with a single median 

 line of hairs; stamens 3-7; styles 3-4; plants annual; waste 

 ground and fields, very common; nat. from Eur. Jan. -Dec. 



Common Chickweed S. media (L.) Vill. 



1. Leaves linear or narrowly lanceolate. 



4. Leaves narrowly elliptical-lanceolate, widest at or above the 

 middle, the margin microscopically papillate; seeds essential- 

 ly smooth; moist ground. May-June S. longijolia Muhl. 



4. Leaves linear-lanceolate, broadest below the middle; margin 

 often sparsely ciliolate; seeds coarsely rugulose-tuberculate; 

 moist ground; adv. from Eur. May- June S. graminca L. 



3. Spergula L. ■ — Spurrey 

 S. arvcnsis L. Fields and waste places, occasional; nat. from Eur. 



4. Spergularia J. & C. Presl — Sand Spurrey 

 S. rubra (L.) J. & C. Presl. Found once in Cook Co., by W. S. 

 Moffatt in 1893. 



5. Sagina L. — Pearl wort 



S. dccumbens (Ell.) Torr. & Gray. Dry ground, occasional. Apr.- 

 May. 



6. Arenaria L. — Sandwort 



{Moehringia L.) 



1. Leaves oval or ovate; valves of the capsules 2-toothed or 2-cleft. 

 2. Leaves oval, obtuse, 1-3 cm long; sepals obtuse, shorter than 

 the petals; seeds smooth; woods in the n. half of the state. 

 May-Jime A. lateriflora L. 



2. Leaves ovate, acute, 2-8 mm long; sepals acuminate, longer than 



the petals; seeds rough; waste ground; adv. from Eur. Apr.- 



June. Thyme-leaved Sandwort A. serpyllijolia L. 



1. Leaves linear-filiform or subulate; valves of the capsule entire. 



3. Leaves rigid, subulate, evergreen, with others fascicled in the 



axils; plant perennial, glabrous; dry wooded bluffs, and on 

 rocks, northern 111., rare. May-July. [A. michauxii (Fenzl) 



Hook.f.] A. stricta Michx. 



3. Leaves soft, linear-filifoiTn; plant annual; pedicels glandular- 

 puberulent; wooded slopes along streams, rare; Cook, Kan- 



