344 ONAGRACEAE (EVENING PRIMROSE FAMILY) 



1896. Puberulent or nearly glabrous: leaves low on the stem, usually lyrately. 

 pinnatifid: calyx-tips not free: capsule 10-25 mm. long. — Wyoming and Colo- 

 rado and far northwestward. 



16. GAURA L. 



Annual, biennial, or perennial herbs, with alternate narrow leaves, and 

 white, pink, or red flowers in terminal spikes or racemes. Calyx-tube narrow, 

 prolonged beyond the ovary, the Umb 4-lobed. Petals clawed, unequal. 

 Stamens usually 8,' declined, each with a small scale at the base. Ovary 

 4-celled; united styles declined; stigma 4-lobed, surrounded by a cup-like 

 border; ovules usually 4, pendulous. Fruit iiut-like, ribbed or angled, in- 

 dehiscent or nearly so, 1-4-seeded. 



Anthers oval; fruits fusiform, S-ribbed 1. G. parviflora. 



Anthers linear or nearly so; fruit strongly 4-angled, at least above. 

 Plants tall, erect, herbaceous. 



Fruit sessile . 2. G. neo-mexicana. 



Fruit with a slender stipe-like base 3. G. coloradensls. 



Plants low, with assurgent stems from a subligneous base • , 4. G. coccinea. 



1. Gaura parviflora Dougl. Hook. Fl. Bor. Am. 1: 208. 1832. Perennial 

 herbs or shrubby plants with much-branched stems: leaves alternate: flowers 

 yellow, axillary: calyx-tube slender, longer than the ovary: ovary 4-celled, 

 elongated; stigma disk-like, entire: capsules elongated, narrowed at the base, 

 more or less curved; seeds sometimes tuberculate. — ^In dry soil; rather infre- 

 quent; from the Missouri to Oregon. 



2. Gaura neo-mexicana Wooton, Bull. Torr. Bot. Club 25: 307. 1898. 

 Stems virgately branched above: leaves lanceolate, subsessile, entire or sin- 

 uate: pubescence subvillous and viscid glandular above: calyx-segments 

 oblong-spatulate, barely longer than the tube: petals obovate, 1 cm. long, 

 rose-pink: style villous below the middle: fruit obovate-pyramidal, sessile. — 

 New Mexico and also reported from Colorado. 



3. Gaura coloradensis Rydb. Bull. Torr. Bot. Club 31: 572. 1904. Her- 

 baceous biennial with fusiform root: stem 5-7 dm. high, finely strigose: leaf- 

 blades narrowly oblanceolate, 6-10 cm. long, callous-denticulate, finely 

 strigose: inflorescence slender and rather lax, 1.5-2 dm. long: calyx-tube about 

 2 cm. long, finely strigose; segments about 1 cm. long, linear-lanceolate, re- 

 flexed: petals about 8 mm. long, spatulate, pink, short-clawed: fruit 8-10 mm. 

 long, fusiform, 4-angled, tapering below into a short and rather slender stipe- 

 like, base. — Northern Colorado. 



4. Gatira coccinea Pursh, Fl. Am. Sept. 733. 1814. Erect or ascending, 

 much branched, canescent or glabrate, 1.5-4 dm. high: leavps oblong, lanceo- 

 late, or linear-oblong, denticulate, repand, or entire, acute or obtuse at the 

 apex, 1.5-3.5 cm. long: flowers red, tiuming scarlet: fruit terete below, 4-sided 

 and narrowed above, canescent, 6-8 mm. long. (G. gkbra Lehm., a nearly 

 glabrous form; G. parmfolia Torr., glabrate and with numerous small linear 

 leaves; G. margincUa Lehm., puberulent, and the leaves and calyx-lobes 

 rather narrower than in the typical species.) — Manitoba and Minnesota to 

 Arizona and Texas. 



16. CIRCAEA L. 



Low, slender, perennial herbs, with opposite petioled leaves and small white 

 flowers in racemes. Calyx-tube slightly prolonged beyond the ovary, its 

 Umb 2-parted. Petals 2, notched. Stamens 2^ alternate with the petals. 

 Ovary 1-2-celled; ovules usually 1 in each cavity. Fruit obovoid, indehis- 

 cent, bristly with hooked hairs. 



Leaves undulate-denticulate; raceme bractless 1. G. pacific*. 



I sharply dentate; bracts present 2l C. alpina. 



1. Circaea pacifica Ach. & Mag. Bot. Zeit. 29: 392. 1871. Mostly glabrous; 



