RUBIACE.E. (MADDER FAMILY.) 225 



pretty plant commemorates Dr. John Mitchell, an early correspondent of Lin- 

 naeus, and an excellent botanist, who resided in Virginia.) 



1. M. ripens, L. Dry woods, creeping about the foot of trees, especially 

 Conifene, throughout our range and southward. June, July. Leaves often 

 variegated with whitish lines Rarely the two flowers are completely conflu- 

 ent into one, with a 10-lobed corolla. 



5. SPERMACOCE, Dill. BUTTON-WEED. 



Calyx-tube short; the limb parted into 4 teeth. Corolla funnel-form or 

 salver-form, valvate in the bud Stamens 4. Stigma or style 2-cleft. Fruit 

 small and dry, 2 celled, 2-seedecl, splitting when ripe into 2 carpels, one of them 

 usually carrying with it the partition, and therefore closed, the other open on 

 the inner face. Small herbs, the bases of the leaves or petioles connected by 

 a bristle-bearing stipular membrane Flowers small, whitish, crowded into 

 sessile axillary whorled clusters or heads. ( Name compounded of cnrepna., seed, 

 and aKwKJ}, a point, probably from the pointed calyx-teeth on the fruit.) 



1. S. glabra, Michx. Glabrous perennial; stems spreading (9 -20' 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. Ohio to Ark., Tex., and Fla. Aug. 



6. DIODIA, Grouov. BUTTON-WEED. 



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. Otherwise resembling Spermacoce. Flowering all summer. (Name 

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



1. D. Virginiana, L Smooth or hairy perennial , stems spreading ( 1 - 

 2 long) ; leaves lanceolate or oblong-lanceolate, sessile . corolla white (' long), 

 the slender tube abruptly expanded into l/ie larye Innb ; sti/le ^.-parted, fruit 

 oblonrj, strom/l i/ furrowed, crowned mostly with 2 slender calyx-teeth Low 

 grounds along streams, southern N. J to Fla., west to Ark. and Tex. 



2. D. teres, Walt. Hairy or minutely pubescent annual ; stem spreading 

 (3-9' long), nearly terete; leaves linear-lanceolate, closely .sessile, rigid ; co- 

 rolla funnel-form (2 -3" long, whitish), with short lobes, not exceeding the long 

 bristles of the stipules : style undivided ; fruit obovate-turbinate, not furrowed , 

 crowned with 4 short calyx-teeth. Sandy soil, N J. to W. 111., Fla., and Tex. 



7. GALIUM, L. BEDSTRAW. CLEAVERS 



Calyx-teeth obsolete. Corolla 4-parted, rarely 3-parted, wheel-shaped, val- 

 vate in the bud. Stamens 4, rarely 3, short. Styles 2. Fruit dry or fleshy, 

 globular, twin, separating when ripe into the 2 seed-like, indehiscent, 1 -seeded 

 carpels. Slender herbs, with small cymose flowers (produced in summer), 

 square stems, and whorled leaves , the roots often containing a red coloring 

 matter. (Name from 70X0, milk, which some species are used to curdle.) 



1. Naturalized species ; fruit dry. 



G. VERUM, L. (YELLOW BKDSTRAW.) Perennial; stems smooth, erect ; 

 leaves 8 or sometimes 6 in the whorls, linear, roughish, soon deflexed ; flowers 



15 



