POIYGONEUA PAEESII. 
Polygonella Parksii sp, aov. Root annual, the plant appearing as a rosette 
in January, beginning to bloom the first of June, and blooming thereafter to the 
first of October; stems slender, simple below, copiously branched above, terete, 
smooth, 60-160 cm. tall, and up to 4 mm. in diameter; branches green, terete, mostly 
1-8 mm. in diiameter, bearing both foliage and flowers; leaves smooth, up to 8 mm* 
long, filifoim to linear-spatulate or narrowly ovate, the wider blades sinuately 
and coarsely toothed, the lower half narrowed and jointed to the ocreae near the top; 
ocreae green, distally pale, lacerate with 4-8 pale to brown bristles, which are 
usuediy 8-3 mm. long; flowers borne in spike-like racemes, some flowers being 
sessile or subsessile, the others short-pedunculate; pedxmcles slender, wiry, mostly 
branched, the pedicels short^ Oq etganiaiae, up to 3 mm* long, mostly spreading to 
recurved; ocreolae imbricated; calyx 5-parted in early bloom with the 8 outer sepals 
shorter but similar to the 3 Inner sepals, which are about 3 ram. long, all 5 sepals 
changing as the fruit develops, the 8 outer sepals spreading or becoming reflexed 
and almost minute in size, the 3 outer sepals becoming shorter, broader, papeiy, 
prominently dark-nerved and concealing the achene or with the styles only exserted, 
then shrinking to half the length and nearly half the breadth of the achene at which 
time each one is appressed to a face of the achene, finally spreading to 
completely disclose achene, or eventually deciduous; achenes light-brown, narrowly 
winged on angles, fully 8 ram, long, and 1.8-1.4 mm, broad. 
Of the American species of Polygonella this species appears to be more closely 
related to P. ciliata Meisn. Among other characteristics it differs from that 
species in its shorter and broader leaves, its shorter achene, and in its achene 
being wholly exposed at maturity. 
IVpe specimen. No. 15500, was collected September 85, t935, in northern 
Atascosa County, Texas, along State Highway No. 66, at about 18 miles north of 
Pleasanton, where it was growing in a flat between two ridges, a foimer valley 
between two dunes. It occurs only where the sand has been newly distffurbed, 
either ly the wind, the plow, or in road grading, the last circimistance being the 
ease at the tjrpe locality, where the new State Highway No, 66 has opened up 
virgin areas. Its known distribution is the Carrizo sand ridges of the counties 
of Atascosa and Wilson, the extreme separation of collection localities being 
about thirty miles. 
This plant is named for its discoverer, my friend and coworker, Ifr. H. B. Parks, 
of the State Apicultural Research Laboratory, near San Antonio, Texas. 
VIC. 
3-17-1937 
