EVENING PRIMROSE FAMILY 205 



Stems 6-15 in. high; leaves linear-oblong or lanceolate, 



toothed, 1-3 in. long; flowers 1-2.5 cm. wide M. serruldta 



Onagra Adanson 1763 Evening Primrose 

 (Gr. onagra, wild ass, from a fancied resemblance of its leaves to an 



ass's ears) 

 PI. 32, fig. 4. 



Sepals 4, united into a tube longer than the ovary, petals 4, yellow, 

 white or pink, separate, stamens 8, ovary 4-celled, stigma 4-cleft, capsule 

 4-angled ; flowers in terminal spikes, opening in the evening ; leaves alter- 

 nate, entire to toothed; annual or biennial. 



1. Calyx tube 1-2 in. long 



a. Petals yellow, 1-2 cm. long O. biennis ' 



b. Petals yellow or pinkish, 2-4 cm. long 0. Hookeri 



2. Calyx tube 2-4 in. long O. Jdmesii 



Pachylophus Spach 18^5 Evening Primrose 

 (Gr. pachys, thick, lophos, crest, from the pod) 



Sepals 4, united into a tube several times longer than the ovary, petals 

 4, white or pink, separate, stamens 8, the alternate longer, stigma 4-cleft, 

 ovary short, capsule pyramidal ; flowers solitary ; leaves basal, entire to 

 \ pinnatifid ; mostly stemless perennials. 

 Plants stemless or rarely with a short stem ; leaves 

 smooth to densely hairy, entire to pinnatifid; flowers 

 2-6 in. wide; calyx tube 2-8 in. long P. caespitosus 



Sphaerostigma Seringe 1828 

 (Gr. sphaira, ball, stigma, spot) 



Sepals 4, united into a short tube, petals 4, yellow, white or rose, 

 separate, stamens 8, ovary 4-celled, stigma globose, capsule 4-angled ; flow- 

 ers axillary and solitary or in terminal spikes ; leaves alternate, entire or 

 toothed ; annual or perennial. 



1. Flowers yellow, often turning red 5\ contortion 



2. Flowers white or rose S. minutiHorum 



Taraxia Nuttall 1840 

 (From its resemblance to Taraxacum) 



Sepals 4, united into a tube longer than the ovary, petals 4, yellow or 

 white, separate, stamens 8, ovary 4-celled, stigma globose, pod 4-grooved 

 or angled; flowers axillary; leaves basal, pinnatifid or entire; stemless 

 perennial. 



