24:6 ORDER XXI. — CARYOPHYLLACE.E. 



Genus III— ARENA'RIA. L. 10—3. 

 (From arena, sand, in which the species grow.) 



Sepals 5, expanding. Petals 5, entire. Stamens almost 

 always 10. Pistils 3. Capsule 3- valved, 1 -celled, many -seeded. 



1. A. serpyllifo'lia, (L.) Stem diffuse, diohotomously divided, re- 

 trorsely pubescent. Leaves ovate, ciliate. Flowers axillary, or in the 

 divisions of the stem, solitary. Sepals hairy, acuminate, lanceolate, 

 somewhat unequal. Petals oval, erect, shorter than the sepals. Sta- 

 mens unequal, shorter than the calyx. Stigmas 3, simple. — White. 0. 

 April — May. Common in dry pastures. 3 — 6 inches. 



2. A. squarro'sa, (Mich.) Stem much divided near the base, glandular 

 pubescent. Leaves short, subulate, the lower ones densely squarrose- 

 imhricate, rather obtuse, upper ones few. Flowers in terminal panicles, 

 few-flowered. Sepals ovate, obtuse, without ntrves. Petals obovate, 

 three times as long as the sepals. — White. IX . April — June. Sand- 

 hills. Common. 6 — 10 inches. 



3. A. stric'ta, (Mich.) Stems diffusely-eaespitose, glabrous, branched 

 from the base. Leaves subulate, linear, erect, 1-nerved, fascicled in the 

 axils. Flowers in a few-flow< red panicle. Sepals ovate, rigid, 3-ribbed. 

 Petals oblong-ovate, longer than the sepals. — White. If. May — June. 

 Mountains. 4 — 6 inches. 



4. A. gla'bra, (Mich.) Stems filiform, decumbent at the base, caespi- 

 tose, glabrous. Leaves linear, spreading, almost setaceous. Flowers 

 8 — 12. Sepals oval, obtuse, membranaceously margined, nerveless. 

 Petals obovate-oblong, twice the length of the sepals. — White. Q. 

 June — July. Mountains. 4 — 6 inches. 



Genus IV.— STELLA' RI A. L. 10—3. (duckweed.) 

 (From stella, a star, the form the petals assume.) 



Sepals 5, expanding, somewhat united at tbe base. Petals 

 5, 2-parted, often perigynous. Stamens 10, or fewer by sup- 

 pression. Pistils 3, or rarely 4. Capsules 3-valved, 1-celled, 

 many-seeded. 



1. S. me'dia, (Smith.) Stem procumbent, with an alternate pubes- 

 cent line. Leaves orate, glabrous. Flowers terminal or axillary. Sep- 

 als hairy. Petal oblong, deeply divided, hypogynous. Stamens 3 — 

 10. Pistils 3. — White. Q. March — Oct. Common. 4 — 8 inches. 



2. S. prostka'ta, (Bald.) Stem procumbent, slightly channeled, fis- 

 tulous, slightly pubescent. Leaves ovate or cordate, acute, smooth, the 

 lower ones <»n Blender eiliate petioles. Flowers solitary. Sepals erect, 

 ovate. Petals deeply divided, segments linear. Stamens usually 7. — 

 While. -... March — April. Flor. 1 — -1 feet long. 



:;. s. l'cr.i :'k\. (Mich.) Stems decumbent, with two opposite pubes- 

 ren! LineSj Leaves sessile, ovate, ciliate. Flowers axillary, solitary. 

 Sepals with membranaceous margin. Petals deeply divided, longer 

 than the sepals. Stamens 10. Pistils & — White. May. In rich soils 

 G — 12 inchi 



4. 8. uniflo'ka, (Walt.) (Armaria glabra of Fll.) Stem branching, 



