Class IV. Order I. 53 



58. HOUSTONIA. 



HOUSTONIA C<ERULEA. L. Bluish Houstonia. 



Root leaves ovate ; stem compound ; first pedun- 

 cles two flo\yered. L. 



Common among the grass in moist ground, flowering in May 

 and afterward. The stems are slender, repeatedly forked, the 

 divisions supporting single flowers. The root leaves are spatu- 

 late or oval, tapering into footstalks ; those of the stem opposite, 

 situated at the forks and elsewhere, lance-oval, the upper ones 

 sessile. Flowers smaller than violets, with which they grow. 

 Segments of the calyx erect, pointed. Corolla bluish white, 

 yellow at the centre, consisting of a slender tube with four ovate, 

 acute, spreading segments. Anthers inserted at the mouth of 

 the cube. Style exserted, stigma bifid. Perennial. 



HOUSTONIA LONGIFOLIA. Willd. Long leaved Houstonia. 



Leaves lanceolate, narrowed at each end ; flowers 

 corymbed. Willd. 



Found in dry soils at Blue hills and elsewhere, not commonly 

 exceeding four or five inches in height. Stem erect, six sided, 

 branching toward the top. Leaves smooth, opposite, lanceolate, 

 somewhat obtuse. Flowers purplish, in a terminal corymb. 

 Calyx segments, oblong, acute ; corolla funnel shaped, divided 

 into four acute spreading segments, pale striped with purple in- 

 side ; stamens inserted in the tube ; style as long as the corolla, 

 stigma two cleft. Blue hills, Milton. June, July. Perennial. 



59. AMMANNIA. 



AMMANNIA HUMILIS. Low Amrnannia. 



Stem procumbent, leaves lanceolate narrowed to a 

 petiole, flowers solitary opposite sessile. 



Stem ascending, leaves oblong lanceolate, rather obtuse, acute 

 at base, and nearly sessile. Flowers small, red, closely sessile 

 in the axils. In wet meadows and on the muddy banks of rivers. 

 August, September. Perennial. 



