Colorado W ekd Seeds 
59 
1. Gaura, Butterfly Weed 
(Gaura L.) 
riiit hard and nut-like, angled or 3-4 ribbed, pointed or blunt, not split- 
ting open at maturity; seeds 1-4 in a fruit. 
Key to Species 
Seeds pointed at tip, distinctly angled 1..0, „occinea 
Seeds blunt, faintly angled 2 . .O. parvifhyrc. 
1. Scarlet Butterfly Weed or Gaura 
{Gaura coccinea Pursh.) (Fig. 104). — 
Seeds pale grass-green in color, thick in 
the middle tapering towards each end, the 
base circular in cross-section, the top 
four-sided and terminating in a point ; 
fruits 4.5-7 mm. long, 2-3 mm. wide in the 
widest part. 
Fig. 104. Scarlet But- 
terfly-weed (Gaura 
coccinea). x 10. 
2. Small-flowered Butterfly Weed or 
Gaura {Gaura parviflora Dougl.) (Fig. 105).— 
Seeds dark honey-yellow, spindle or ten-pin 
shaped, 8-veined, faintly angled at the large 
snd, 6-8.5 mm. long, 1.7-2.5 mm. wide in the 
'widest part. 
Fig. 105. Small- 
flowered Butter- 
fly-weed (Gaura 
parviflora). x 5. 
2, Evening Primrose 
{Oenothera L.) 
Fruit a capsule, 4-veined ; seeds numer- 
ous, prismatic, angled. 
Evening Primrose {Oenothera strigosa 
Rydh.) Seeds dull, russet in color, rough, 
angled, irregular, prism-shaped, 1.5-2. 5 
mm. long, .6-1.2 mm. wide in the wide-t 
part. 
Fig. 106. Evening 
Primrose (Oenothera 
strigosa). x 11 . 
