INDEX 



109 



Narcissus, 19 

 Neurospora, 13 



New Zealand, introgression in, 80 

 Nicoiiana alata X A^. Langsdorffii, 

 31 



description of, 32 



illustrated, 72, 92 



Orange Island, 64 



Origin of domesticated plants, role of 



introgression in, 66 

 Osborn, 20 

 Ostenfeld, 1 

 Ownbey, 76 



Para rubber, see Hevea 



Parodi, 67 



Pastoral agriculture, effect upon in- 

 trogression, 79 



Pictorialized scatter diagrams, 83 

 illustrated by example, 84, 94 



Pinus, 63 



Planta, a hypothetical genus, evolu- 

 tion in, 71 



Polygraphic analysis, defined, 83 



Primula, 62 



Radiate indicators, 88 



Randolph, 2 



Raunkiaer, 89 



Recombination spindle, 52, 53, 55 



defined, 33 



in Nicotiana, illustrated, 34 



theoretical, illustrated, 40 

 Reed, 2, 4 

 Rehder, 22 

 RHey, 2, 7, 10, 80, 86, 89, 90, 94 



Saccharum, 20 

 Salicornia, 91 

 Salvia, 62 

 Sargent, 80 

 Sauer, 75 

 Scatter diagrams, 83 



pictorialized, 83 



superiority to correlation coeffi- 

 cients, 83 

 Seibert, 78 

 Silene, 62 

 SmaU, 7 



Small and Alexander, 7 

 Species, barriers between, 58 

 Standardized photographs, details of 



technique, 92 

 Sugar maple, 66 

 Sunflower, see Helianthus 



Tradescantia canaliculata, 16 

 Tradescantia subaspera, 16 

 TurriU, 62 



Vaccinium, 12 

 Valentine, 62 

 Vavilov, 67 

 Viosca, 2, 6, 17 



Walker, 83 



Weeds, origin of, 66 



Wide crosses, 20 



Wiegand, 12 



Wilmott, 91 



Woodson, 61, 62, 64, 102 



Zea X Tripsacum, 20, 100 

 Zirkle, 21 



