106 



UETICACEAE. 



4. PARIETARIA L. 



Herbs, with alternate entire 3-nerved petioled leaves, no stipules, and 

 axillary glomerate polygamous flowers, involuerate by leafy bracts. Calyx of 

 the staminate flowers 4-parted or of 4 (rarely 3) distinct sepals. Fertile 

 flowers with a 4-lobed calyx investing the ovary, a short or slender style, and 

 a penicillate stigma. Achene enclosed by the pistillate calyx. [Ancient Latin, 

 referring to the growth of some species on walls.] About 7 species, widely 

 distributed. Type species: Parietaria officinalis L. 



1. P. floridana. 



2. P. officinalis. 



Leaves obtuse or bluntly acuminate ; bracts linear : native species. 

 Leaves acute to acuminate ; bracts ovate ; introduced. 



1. Parietaria floridana Nutt. 

 EED PKLLITORY. (Fig. 124.) An- 

 nual, slender, finely but often 

 densely puberulent. Stems ascend- 

 ing or spreading, 4"-20" long, 

 often much branched; leaves thin, 

 flaccid, numerous, usually ovate to 

 subrhombic, 2' long or less, blunt 

 at the apex or sometimes short- 

 acuminate but obtuse, entire, 

 mostly obtuse at the base ; petioles 

 filiform ; bracts of the involucre 

 linear or linear-lanceolate, 2" long, 

 acute; sepals lanceolate, thin, acute 

 or acutish; achenes ovoid, shining, 

 [P. debilis floridana Nutt. ; P. de- 

 It His of Eein, Hemsley, H. B. Small 

 and Moore; ?P. pennsylvanica of 

 Hemsley.] 



Common in sandy soil and rocky 

 shaded situations. Native. Flowers 

 nearly throughout the year. South- 

 eastern United States. Its seeds 

 probably transported to Bermuda by 

 the wind. 



2. Parietaria officinalis L. WHITE 

 PELLITORY. (Fig. 125.) Perennial, tufted, 

 finely pubescent ; stems subherbaceous, 

 branched, 1 high or less. Leaves rather 

 thin, ovate to ovate-lanceolate, V-2' long, 

 acutish to acuminate at the apex, mostly 

 obtuse at the base, slender-petioled ; invo- 

 lucral bracts ovate to oblong ; sepals ovate ; 

 achenes about i" long. [P. alba of H. B. 

 Small.] 



On walls and in waste grounds, frequent. 

 Naturalized from Europe. Flowers nearly 

 throughout the year. 



