FIFTEEN- AND SIXTEEN-CHROMOSOME OENOTHERA MUTANTS IO5 
of 0. lata are rather long, but those of the two mutants were relatively 
short. Lamarckiana and lata are almost invariably annual in this 
climate (when seeds are sown in January and rosettes transplanted 
in May) and flower quite early, the latter frequently earlier than the 
former. No. 3474 bloomed quite late, about the middle of August. 
The buds, seed-capsules, stem and branches of this plant were covered 
with long hair. The petals of the open flower did not have the ordinary 
crumpled appearance characteristic of 0. lata, but were creased longi- 
tudinally, much as if the flower had been drawn through a very small 
finger ring. Many flowers had five or more petals. The stigmas 
were very irregularly branched, much more so than in 0. lata, and an 
anther occasionally bore a rudimentary petal. Somatic metaphase 
groups from Nos. 3474 and 5414 are shown in Figs. Sa, 8b and 8c. 
Fig. 8. a and b, unidentified lata-like mutant, plant No, 3474, C.S.H., 1908 
Offspring of O. Lamarckiana X O. Lamarckiana. Polar view of metaphase figures 
from transverse sections of root-tips, showing 16 chromosomes. c, unidentified 
mutant, plant No. 5414, C.S.H., 1910. Offspring of 0. lata, selfed. Polar view 
of metaphase figure from transverse section of root-tip, showing 16 chromosomes. 
2. The Dwarf Form Produced by O. lata, Selfed 
This plant, No. 5414 (1910), was abnormal in appearance in all 
stages of development. It is shown as a greenhouse rosette in Fig. ga, 
and as a full-grown garden rosette in b, the diameter of the latter not 
exceeding one fourth of the diameter of a full-grown lata rosette. The 
plant came to flower late in the season on a very short stem and it is 
i mpossible to state whether this was due to the character of dwarfness 
(suggested in the rosette) or to a depauperate, abnormal condition. 
