KNOWLEDGE OF THE MUTATING OENOTHEEAS, 67 



Plate 6. 



Fig. 71. Rosette of 0. biennis x 0. laevifolia^ Fj, broad-leaved type. Cf. fig. 69. 



72. Rosette of 0. biennis x 0. laevifolia^ Fj, li arrow-leaved type. C/1 fig. 70. 



73. Intermediate type from 0. biennis x O. laevifolia^ Fi, another cross. 



74. Flowering shoot of 0. biennis X 0. Lamarckiana^ Fj^ veluttna type. 



75. Flowering shoot of 0. biennis x O. Lamarckiana^ Fi, /«^/a type. 



76. Buds, two-thirds natural size, from 0. biennis x 0. Lamarckiana, Yy (velutina). Cf. bracts 



and buds with fig. 53 (0. biennis). The buds are larger and more hairy, the bracts more 

 nearly entire. 



77. Shoot showing flowers, capsules, and bracts from 0. biennis x 0. laevifolia. 



78. Rosette of 0. Lamarckiana x 0, biennis^ F^ broad-leaved type. Cf. fig. 69. 



79. Rosette of 0. nanella x 0. biennis, F^. 



80. (9, Lamarckiana x O. biennis, shoot in 



fruit 



81. Pan of seedlings of 0. biennis X O. nanella^ Fj. C/*. 



82. Pan of seedlings of 0. nanella x 0. biennis, Fj. 



83. 0. nanella, pan of young seedlings. C/*. figs. 81 and 



c/. 



Note added January/ ^nd, 1913. 



The recent important paper of N. Heribert-Nilsson (1912) has shown that in an 

 independent race of O. LamarcMana obtained from a garden in Southern Sweden, which 

 differs in some respects from the race of DeVries, mutations are produced which are 

 parallel to, though differing from, the DeVriesian mutants. Thus it is further shown 

 that O. LamarcMana^ like ordinary wild species, contains various elementary species, 

 and new difficulties arise before those {e. g., B. M. Davis) who would derive all the races 

 of 0. Lamarcldana from a single (hypothetical) source. 



Nilsson also expresses the view, with which I am in agreement, that from an 

 evolutionary standpoint it is immaterial just what forms may have taken part in the 

 complex ancestry of 0. Lamarckiana, 



The valuable data of Nilsson's paper, and particularly his description of the behaviour 

 of a new giant type, are of great interest. His explanation of the mutation phenomena 

 without regard to the cytological facts has, however, led him into theoretical errors 

 which might otherwise have been avoided, but these in no way detract from the useful- 

 ness of the mass of breeding data contributed. I shall refer in greater detail io these 

 giant forms in a paper now in the press in the * Biologisches Centralblatt.' 



il. H. G. 



