318 University of California Publications in Botany [A^ol. 5 



and Hayes (1912) obtained only weak and stunted plants from this 

 cross. Lock refrains from making any general statement concerning 

 the resemblance of the hybrid to one or the other parent, although he 

 apparently found a predominating influence of paniculata in deter- 

 mining flower shape and color. All observers are agreed on the total 

 sterility of the hybrid. According to Lock, fruits were produced which 

 contained a few seeds but these failed to germinate. 



N. glauca X N. Langsdorffii sometimes gives hybrids, but only 

 with great difficulty (Gartner, p. 144). In one place (p. 222) Gart- 

 ner describes it as resembling glauca, but in other places (pp. 267, 

 402) it is listed among infertile hybrids which resemble the male 

 parent. It is completely sterile (p. 389). Focke (1881) draws the 

 conclusion that the hybrid resembles glauca, but to us it seems that 

 Gartner intended to convey the impression that it was more like 

 Langsdorffii in its characters. In reaching this conclusion we have 

 been guided by the fact that Gartner's statements as to hybrid and 

 parental resemblances on p. 222 contain so many other contradictions 

 to subsequent statements as to make it extremely probable that they 

 were due to a slip of the pen. 



N. suaveolens X N. Langsdorffii is easily obtained, but absolutely 

 infertile (Gartner, p. 194). In spite of one contrary statement (Gart- 

 ner, p. 222), we may judge that it strongly resembles suaveolens in 

 most of its characters. Gartner states on one page (p. 258) that it 

 resembles the maternal parent so closely that were it not for its total 

 sterility there might be doubt as to its hybrid nature. In another 

 place (p. 362) he states that it differs from suaveolens only in it.s ster- 

 ility, in the separation of the stamen filaments from the tube of the 

 corolla, and in the bluish color of the anthers. 



N. vincaeflora X N. Langsdorffii is listed by Gartner in one place 

 (p. 222) among those patroclinous in type, but in all others places 

 its resemblance to vincaeflora is emphasized. On page 258 the re- 

 semblance to vincaeflora is reported to be just as striking as that of 

 suaveolens X Langsdorffii to suaveolens. The hybrid is totally sterile 

 (Gartner, p. 471). 



N. glutinosa X N. Tahacum, according to Gartner (p. 471), is 

 decidedly like the male parent, but the results of Kolreuter and 

 Naudin appear to establish an intermediate behavior for crosses be- 

 tween glutinosa and various varieties of Tahacum. Gartner (p. 402) 

 states that reciprocal crosses of grandiflora X glutinosa and chinensis 

 X glutinosa reproduce throughout grandiflora and chinensis. 



