[Vol. 8 
116 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
grams. The species so segregated are certainly not to be ar- 
ranged in a linear series but it is believed that they are historically 
united by some common ancestor. In L. Schaffneri of this 
group the greatest degree of union possible occurs between the 
rays and a radiately marked scale is produced. 
Summary.—The more important phylogenetic conclusions 
reached in the preceding paragraphs may be summed up as fol- 
lows: 
1. The immediate ancestors of this genus are believed to have 
been entirely herbaceous. 
2. Rosette-forming species in which the terminal bud remains 
comparatively undeveloped are held to have been rather re- 
cently derived from species in which there is no inhibition of the 
terminal bud. 
3. From the lyrate-pinnatifid type of radical leaves have been 
evolved the entire linear or suborbicular leaves. 
4. Cauline leaves with auriculate bases are considered more 
primitive than those which are narrowed to the base. 
5. Yellow is the predominating petal color in primitive species, 
while white, red, or purple is of more recent origin. The obovate 
petal is more primitive than the narrower forms. 
6. The species of Lesquerella having abruptly dilated filament- 
bases are to be considered more primitive in this character than 
those with gradually dilated or linear filaments. 
7. Within the genus there is not a great deal of variation in 
the nectar glands, but the tendency seems to be toward reduc- 
tion. 
8. The recurved or S-shaped pedicels are thought to have 
been developed from straight or curved-ascending forms. 
9. The length of the gynophore or stipe, when present, seems 
to decrease with further development, yet it may not have been 
present in the ancestor of this genus. 
10. Glabrous, spherical capsules are considered primitive, at 
least in the section Eulesquerella. 
11. The course of evolution has been in Mix case from the 
many- to the few-ovuled forms. 
12. Seeds provided with a narrow wing or margin are believed 
to have prevailed among the most primitive species. In a few 
