US MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 



[Plate 36.] 

 36. Polygonum Rayi Babington. 



Polygonum Rayi Babington, Man. Brit. Bot. Ed. 2, 275 (1847) ; Meisner in DC. 

 Prodr. 14: 88. 



Perennial or annual, glabrous, glaucescent throughout or sometimes bright green. 

 Stem prostrate, .5-6 dm. long, ridged, simple or much branched either from the base or 

 throughout, slender or stout ; leaves varying from ovate to ovate-lanceolate or oblong, 

 .5-4 cm. long, .2-1 cm. broad, shorter than the internodes, except on young branches, 

 rather thin or somewhat fleshy, usually flat, acute or obtusish, sometimes inconspicu- 

 ously sub-parallel nerved above, acuminate at the base, not revolute, articulation at 

 the ocreae not prominent; ocreae funnelform, oblique, .5-8 cm. long, two-parted, at 

 length lacerate, silvery, becoming fuscous and glaucous at the base; inflorescence axillary, 

 consisting of clusters bearing from two to five flowers ; pedicels slender, 3-4 mm. long ; 

 calyx 4 mm. long, five-parted to below the middle, the segments oblong, obtuse, sub- 

 petaloid, with whitish borders ; stamens eight, included ; style 5 mm. long, three-parted 

 to the base; achene triquetrous, 3.5-5.5 mm. long, ovoid, inclined to be acute, dark chest- 

 nut-colored, slightly granular but mostly shining, conspicuously surpassing the calyx. 



Prince Edward's Island and New Brunswick to Vancouver Island, southward along 

 the Atlantic coast to Virginia. Probably naturalized from Europe. 



