446 FLORA OF TEXAS. 



bearded within ; stamens inserted above the middle of the 

 tube, anthers oblong, obtuse; stigma globose, surrounded 

 by a cup-shaped membrane; /o//iWe5 slender; seeds in a 

 single row, terete, truncated at each end, naked.— Erect 

 branching perennial herbsy with alternate leaves, and small 

 pale-blue /ozyers in a terminal panicle. 



A. CILIATA, Walt. Stem hairy, at length much branched 

 above; leaves very numerous, linear or linear-lanceolate, 

 acute at each end, fringed on the margins; corolla smooth. 

 Dry sandy soil. April and May. Stem at length 2°-3° 

 high ; leaves 1-2' long; corolla pale blue or white ;/o/ZiWe5 

 more slender than those of the preceding. 



A. SALiciFOLiA, Ph. Very glabrous and lance-elliptic, 

 acuminate at each end, conspicuously petiolate; calyx-seg- 

 ments triangular acute ; corolla-tvibe glabrous outside or 

 more or less woolly ; floiuers blue. 



96. MILKWEED FAMILY. Order, Asclepiadace^. 



Erect or twining herbs or shrubs, with milky juice, en- 

 tire commonly opposite leaves without stipules, and umbel- 

 late or cjmose floivers ; ca??/.-?; 5-parted, persistent; corolla 

 5-parted, mostly valvate in the bud, hypogynous, deciduous ; 

 stamens 5, inserted on the base of the coroWa, the filaments 

 united in a tube (gynostegium) which incloses the ovaries, 

 and bears appendages of various forms, which are collec- 

 tively termed the stamineal crown; anthers erect, 2-4-celled, 

 expanding above into a thin membrane; polle7i united in 

 flattened waxy pear-shaped masses, which are equal in 

 number to the cells of the anthers, and fixed to the five 

 angular processes of the stigma by a slender stalk, pendu- 

 lous or horizontal; styles 2, the thick and fleshy stigma 

 common to both ; fruit a follicle ; seeds anatropous, imbri- 

 cated on the thick and at length free placenta, and com- 

 monly bearing at the hilum a tuft of hairs (cotna) ; embryo 

 straight in thin albumen ; cotyledons leafy. 



