268 Retrograde Varieties 



is a hybrid sundew between D. anglica and D. 

 rotundifolia. Primula variabilis is a hybrid 

 between the two common primroses, P. offici- 

 nalis and P. grandiflora. The willow-herb 

 (Epilobium), the self-heal (Brunella) and the 

 yellow pond-lilies (Nuphar) afford other in- 

 stances of constant wild hybrids. 



Macfarlane has discovered a natural hybrid 

 between two species of sundew in the swamps 

 near Atco, N. J. The parents, D. intermedia 

 and D. filiformis, were growing abundantly all 

 around, but of the hybrid only a group of eleven 

 plants was found. A detailed comparison of 

 the hybrid with its parents demonstrated a 

 minute blending of the anatomical peculiarities 

 of the parental species. 



Luther Burbank of Santa Rosa, California, 

 has produced a great many hybrid brambles, 

 the qualities of which in many respects surpass 

 those of the wild species. Most of them are 

 only propagated by cuttings and layers, not 

 being stable from seed. But some crosses be- 

 tween the blackberry and the raspberry (R. 

 fruticosus and R. Idaeus) which bear good 

 fruit and have become quite popular, are so 

 fixed in their type as to reproduce their com- 

 posite characters from seed with as much regu- 

 larity as the species of Rubus found in nature. 

 Among them are the " Phenomenal " and the 



