134 MISSOURI BOTANICAL GARDEN. 



barrel-shaped, not usually squarish, thick; anthers dry and 

 sterile; petals much crumpled in the bud, arranged so as to 

 make it usually one-sided. 



The 0. lata from Liverpool, England, is a stronger form 

 which has less difficulty in forming a stalk, having buds of 

 normal squarish shape, and producing a considerable amount 

 of good pollen, so that self-pollination can be effected with- 

 out difficulty. This brings it very close to 0. semilata, but 

 the characters of the rosette and stem leaves are those- of 

 0. lata rather than 0. semilata. 



Oenothera gigas DeVries. 



See under O. Lamarckiana. Die Mutationstheorie. 1 : 192. pi. 2, colored; 

 1 :226. /. 60, flowering shoot; 1 : 228. /. 62, rosette leaf; 1 : 229. 

 /. 63, young rosette; 1 : 230. /. 66, very young rosette; 1 : 321. /. 101, 

 fruits; 2 : 496. pi. 3, colored. 



Larger than the other mutants in nearly all its parts. 

 Rosettes of very large, crinkled leaves, very variable in shape 

 but usually very broad, sometimes nearly orbicular, sharply 

 narrowed to petiole and much crinkled. Internodes and cap- 

 sules shorter and thicker than in 0. Lamarckiana. Bud cone 

 and hypanthium thicker, petals broader. 0. gigas nanella is 

 a dwarf sub-type of 0. gigas. 



Oenothera nanella DeVries. 



See under 0. Lamarckiana. Die Mutationstheorie. 1 : 165. /. ^5, whole 

 plants; 1 : 256. /. 77, flowering shoot; 1 : 257. /. 78, very young 

 rosette; 1 : 260. /. 79, young rosettes; 1 : 267. /. 80, buds on stem 

 tip; 2:240. pi. i, colored; 2 : 496. pi. 3, colored. 



Rosette leaves variable in shape, small, usually broad and 

 very obtuse, not much crinkled, sessile or with very short 

 petioles, forming a compact rosette. Internodes very short, 

 BO that the plant usually reaches a height of only 10 to 20 

 cm. Flowers almost full size. 



Oenothera laevifolia DeVries. 



Die Mutationstheorie. 1 : 218. /. 56, flowering shoot; 1 : 221. /. 69, 

 small flowers. 



Rosette leaves more narrowly lanceolate than in 0. La- 

 marckiana, of uniform width for the greater part of their 



