JOURNAL 



OF 



The New York Botanical Garden 



Vol. XXX June, 1929 No. 354 



THE FULVOUS DAYLILIES— I 



1. The Hemerocallis fulva clon Europa 

 The oldest and the best-known of the fulvous daylilies is the 

 one commonly cultivated under the name Hemerocallis fulva L. 

 This single-flowered daylily was described by Lobel in 1576 (His- 

 toria) as having cinnabar-red coloring in the flowers and as being 

 in this particular very distinct from the yellow-flowered daylily 

 (H. flava), which was also then in cultivation in Europe. In 

 1601, Clusius (Plantarum Historia) states that this plant was 

 being grown in many gardens throughout Austria and Germany. 

 Nearly two hundred years later, Linnaeus (1753) considered this 

 daylily as a hybrid, but a few years afterward (Species Plan- 

 tarum, ed. 2, 1762) he gave to it the specific rank and the name 

 Hemerocallis fulva which have since been accorded to it. 



But the plants of this particular daylily do not produce seeds to 

 any kind of pollination possible for them alone. They are evi- 

 dently never able to do so because of a complete self-incompati- 

 bility in the processes of fertilization. The propagation of this 

 daylily is by division. All the plants of it are merely branches 

 derived from one original seedling and hence they constitute a 

 clou and not a species or a variety that reproduces true to type by 

 seeds. This distinction was not recognized by Linnaeus, but it is 

 necessary to make the distinction if one is clearly to understand 

 the true status of those groups of plants, both in culture and in 

 the wild, that have arisen from a single individual by repeated 

 vegetative division. The Hemerocallis fulva of Linnaeus, which 

 was in cultivation in Europe for at least one hundred and eighty- 

 six years before his date of naming it as a species (1576 to 1762), 

 and which has continued in cultivation for one hundred and 



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