RUBIACEAE (MADDER FAMILY) 



751 



911. S. glabra. 



912. D. virginiana. 



ters or heads. (Name compounded of <rir{pfjia, 

 seed, and CIKWK?;, a point, probably from the pointed 

 calyx-teeth on the fruit. ) 



1. S. glabra Michx. Glabrous perennial; 

 stems spreading, 2-5 dm. long ; leaves oblong- 

 lanceolate ; heads many-flowered ; corolla little 

 exceeding the calyx, bearded in the throat, 

 bearing the anthers at its base ; filaments and 



style hardly any. River-banks, s. O. to 111., Ark., Tex., and Fla. Aug. 



FIG. 911. 



5. DI6DIA [Gronov.] L. BUTTONWEED 



Calyx-teeth 2-5, often unequal. Fruit 2 (rarely 3) -celled, the crustaceous 

 carpels into which it splits all closed and indehiscent. Flowers 1-3 in each 

 axil. Resembling Spermacoce. Flowering all summer. (Name from SfoSos, 

 a thoroughfare ; the species often growing by the wayside. ) 



1 . D. virginiana L. Smooth or hairy perennial ; stems spreading, 3-6 dm. 

 long ; leaves lanceolate or oblong-lanceolate, sessile ; corolla white, 1 cm. long, 

 the slender tube abruptly expanded into the 



large limb ; style 2-parted ; fruit ellipsoid, 

 strongly furrowed, crowned mostly with 

 2 slender calyx-teeth. Low grounds along 

 streams, s. N. J. to Fla., w; to Mo., Ark., 

 and Tex. FIG. 912. 



2. D. tdres Walt. Hairy or minutely 

 pubescent annual ; stem spreading, 1-8 dm. 

 long, nearly terete ; leaves linear-lance- 

 olate, closely sessile, rigid ; corolla funnel- 

 form, 4-6 mm. long, whitish, with short lobes, not exceeding the long bristles 

 of the stipules ; style undivided ; fruit obovoid-turbinate, not furrowed, crowned 

 with 4 short calyx-teeth. Sandy shores and barrens, Ct. to Fla.; and from O. 

 to Kan., and southw. (Mex., W. I.) 



6. MITCHELLA L. PARTRIDGE BERRY 



Flowers in pairs, with their ovaries united. Calyx 4-toothed. Corolla-lobes 

 spreading, densely bearded inside, valvate in the bud. Style 1 ; stigmas 4, 

 linear. Fruit a berry-like double drupe, crowned with the calyx-teeth of the two 

 flowers, with 4 small seed-like bony nutlets to each flower. A smooth and 

 trailing small evergreen herb, with round-ovate and shining petioled leaves, 

 minute stipules, white fragrant flowers often tinged with purple, and scarlet 

 (rarely whitish) edible (but nearly tasteless) berries, which remain over winter. 

 Flowers occasionally 3-6-merous, always dimorphous ; all those of some indi- 

 viduals having exserted stamens and included stigmas ; of others, included 

 stamens and exserted style. (This very pretty plant commemorates Dr. John 

 Mitchell, an early correspondent of Linnaeus, and an excellent botanist, who 

 resided in Virginia.) 



1 . M. repens L. Dry woods, creeping about the bases of trees, especially 

 Coni ferae, throughout our range, and southw. June, July. Leaves often 

 variegated with whitish lines. Rarely the two flowers completely confluent into 

 one, with a 10-lobed corolla. * 



7. CEPHALANTHUS L. BUTTONBUSH 



Calyx-tube inversely pyramidal, the limb 4-toothed. Corolla-teeth imbricated 

 in the bud. Style thread-form, much protruded. Stigma capitate. Fruit small, 

 at length splitting from the base upward into 2-4 closed 1-seeded portions. 

 Shrubs or small trees, with the white flowers densely aggregated in spherical 

 peduncled heads. (Name composed of /ce0o\^, a head, and &vdos, a flower.} 



