596 



ONAGRACEAE. 



Vol. II. 



4. Oenothera Oakesiana Robbins. Oakes' Evening-Primrose. Fig. 3040. 



Oenothera biennis var. Oakesiana A. Gray, Man Ed 



5, 178. 1867. 

 Oenothera Oakesiana Robbins; S. Wats. Bibl. Indtx 



i: 383. 1878. 

 Onagra Oakesiana Britton, Mem. Torn Club 5 : 233. 



1894. 



Resembling the two preceding species, usually 

 annual, dull green, pubescent with appressed 

 velvety hairs. Stem i°-4° tall, mostly simple; 

 leaves narrow, the basal narrowly oblanceolate] 

 3'-io' long, the cauline lanceolate or linear-lan- 

 ceolate, all acute, distantly dentate, sessile or 

 short-petioled ; flowers yellow, nocturnal, I'-ii' 

 broad; spikes 4'-2o' long; calyx villous, its tube 

 about l' long, its segments linear-lanceolate, one- 

 half as long as the tube, rather prominently ap- 

 pendaged below the tip; petals obovate, i'-i' long; 

 capsule linear-pyramidal, gradually narrowed to 

 the summit, li'-li' long, 4-sided, curved; seeds 

 prismatic, about l" long, the faces reticulated. 



Sandy soil, Massachusetts to Long Island. Summer. 



Oenothera strigosa Rydb. (O. canovirens Steele), 

 of the Central States, ranging eastward to Illinois ; 

 resembles O. Oakesiana but has some long hairs and 

 unappendaged calyx-segments. It may not be distinct 

 froffi 0. biennis. 



5. Oenothera argillicola ^lackenzie. Narrow- 

 leaved Evening-Primrose. Fig. 3041. 



Oe, argillicola Mackenzie, Torreya 4: 56. 1904. 



Onagra argillicola Mackenzie, Torreya 4: 57. 1904. 



Stems several from the same root, finely puberu- 

 lent, 3°-4i° high. Rosette-leaves oblanceolate, 2j'-6' 

 long, 8" wide or less, acute, sinuate, tapering into 

 long petioles ; stem-leaves Hnear-lanceolate, 2i'-2V 

 long, glabrous, or slightly puberulent ; calyx-tube 

 very slender, glabrous, i}'-ij' long; petals obcordate, 

 crenulate, li'-ij' long; capsules glabrous, gradually 

 tapering upward from the base, about i' long. 



In rocky soil, Virginia and West Virginia. July-Sept. 



8. RAIMANNIA Rose, Contr. Nat. Herb. 8: 330. 1905. 



Usually low annual biennial or perennial caulescent herbs, with prostrate or erect stems. 

 Leaves alternate, sinuate or pinnatifid. Flowers perfect, yellow, axillary, or sometimes in 

 terminal spikes, nocturnal; buds erect. Calyx-tube elongated, sometimes filiform, terete; 

 calyx-segments 4, finally reflexed, deciduous. Petals 4, spreading. Stamens 8, equal in 

 length; filaments filiform; anthers linear. Ovary 4-celled, elongated; united styles filiform; 

 stigma deeply 4-cleft ; ovules numerous, in 2 rows, ascending. Capsules usually narrowly 

 cylindric, sometimes slightly tapering, spreading or ascending, obtusely 4-angled, loculicidal. 

 Seeds numerous, in 2 rows, terete, crowned by a tubercle. [Name in honor of Rud. Raimann, 

 a monographer of this family.] 



About 20 species, in North and South America. Type species: Raimannia lacin'.ata (Hill) Rose. 



Flowers axillary. 



Silvery-pubescent with appressed or ascending hairs ; seeds striate. i. R. humifusa. 



Glabrous or sparingly hirsute-pubescent ; seeds pitted. 2. R. laciniata. 



Flowers in terminal bracted spikes. 3. R. rhombipetala. 



