THE MUTATIONS OF OENOTHERA STENOMERES 
H. H. Bartlett 
This preliminary article on the mutations of Oenothera stenomeres 
Bartlett is presented now in order to substantiate certain statements 
in a paper contributed by the writer to the symposium on the genetic 
relationships of organisms, held at the recent Philadelphia meeting of 
the Botanical Society of America. The papers of the symposium will 
appear in this Journal next month. Some of the mutations of Oe. 
pratincola Bartlett, which were also referred to, are dealt with in 
an article which have been published elsewhere.^ A brief statement 
in regard to the mutability of Oe. stenomeres may be found in an earlier 
number of this journaP to which reference must be made for a full 
characterization of the species. The two mutations are mut. lasio- 
petala and mut. gigas; the former has occurred five times in the 
cultures of the first four generations, the latter but once. These cul- 
tures may be summarized as follows: 
P Unknown. 
Fi 1910 A single plant, culture No. 32, transplanted into the garden from the 
wild and self-pollinated; f. typica. 
F2 191 1 °o Progeny of No. 32, 10 plants; f. typica. 
F3 191 2 00 Progeny of No. 32-4, 8 plants; f. typica. 
F3 1914 Progeny of No. 32-4, 4 plants; 3 mut. lasiopetala, i f. typica. 
F3 1912 00 Progeny of No. 32-6, 8 plants; f. typica. 
F3 1 9 14 Progeny of No. 32-6, 80 plants; f. typica. 
F3 1914 Progeny of No. 32-9, 7 plants; i dwarf, 6 f. typica. 
F4 1913 Progeny of No. 32-4-6, 106 plants; i self-sterile, i mut. lasiopetala, 
I mut. gigas, 103 f. typica. 
F4 1914 Progeny of No. 32-4-6, 96 plants; I mut. lasiopetala, 95 f. typica. 
The object of growing the cultures of 1910, 191 1 and 1912 was 
primarily systematic, and the garden space was small. Consequently 
only a few plants were brought to maturity. In the summary above 
I have indicated by the sign 00 the cultures in which germination 
1 Bartlett, H. H. Additional Evidence of Mutation in Oenothera. Bot. Gaz. 
59: 81-123. 1915. 
2 Bartlett, H. H. An Account of the Cruciate-flowered Oenotheras of the 
Subgenus Onagra. Amer. Journ. Bot. i: 226-243. I9I4- 
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