1911] MACDOUGAL—OVARIAL TREATMENTS 245 
two in other publications) that was distinguishable as soon as the 
cotyledons had attained full expansion, these organs being broader 
and of a more vivid green, which was also characteristic of the 
leaves of the rosette. The plants were kept under close oberva- 
tion until maturity, and guarded seeds were obtained. Every 
Fic. 1.—a, a, Rosettes of induced derivatives of Oenothera biennis three months 
old; b, rosette of O. biennis of same age. : 
Stage of their ontogeny was characterized by features which allowed 
them to be readily distinguishable from the parent. Successive 
Senerations were cultivated in the New York Botanical Garden, 
in the open, under lath shelters, in glass houses, and at the high 
mountain plantation of the Desert Laboratory, as well as at the 
Acclimatization Laboratory, Carmel, California, the close of the 
fifth generation now having been reached, with no diminution of 
the degree of divergence by which the new form was first recog- 
nized. (See figs. 1 and 2.) 
The following formal descriptions were prepared from plants 
8rown in New York under conditions as nearly identical as it was 
Possible to secure them: 
OENOTHERA BIENNIS, average form. 
Mature rosette—Leaves ample, rather copiously fine pubescent, 
the larger ones about 27 cm. long, 6-7 cm. wide; blades oblong 
to elliptic, or slightly broadened upward, unevenly repand-denticu- 
ate and most rather jagged toothed near the base, the petioles 
relatively stout. 
