KRrriSCIIl-: Hl-rrHACHTUNGEN DER LAETA-VELUTINA-SPALTUNG 341 



Furthermore, the colour of the nerve is segregating independent of the 

 ktcta and velutina characters. Thus a red-nerved O. Lamarckiana 

 gives rise to eight kinds of gametes just as any other triple-hybrid, 

 and cannot, therefore, be regarded as a nuclear chimaera. All mo- 

 nohybrids should be regarded as nuclear chimaeras if the definition 

 of LoTSY was correct. But Lotsy has apparently only given another 

 name to the fundamental Mendelian phenomenon which we are used 

 to call the formation of pure gametes. The establishing of a de 

 Vriesian segregation by Lotsy in Oenothera contrary to the Mendeliaii 

 segregation cannot be considered a valid one. 



The peculiar phenomena of variation in O. Lamarckiana and in 

 the Oenothera crosses are due to peculiarities in terminology when 

 critically examined. Mutation is conipUcated segregation (repulsion, 

 homozygote elemination, heterogamy), complex inheritance is pleio- 

 tropy, nuclear chimaera means the formation of pure gametes, and 

 abnormal ratios are due to certation (that is, a different power of 

 growth of genotypically different pollen tubes) as I have recently 

 shown. Nothing seems to stay in the way of an analysis of O. La- 

 marckiana according to the principles usually employed, viz. the fac- 

 torial analysis. 



ZITIERTE LITERATUR. 



1. Heribert-Nilsson, N. 191.^. Die Spaltungserscheinungen der Oenothera La- 



marckiana. — Lunds Universitets Ârsskrift, N. F., Afd. 2, 12. 132 S. 



2. — 1920. Zuwachsgeschwindigkeit der Pollenschläuche und gestörte Mendel- 



zahlen bei Oenothera Lamarckiana. — Hereditas /, S. 41 — 67. 



3. Lehmann, E. 1920. Oenothera jallax Renner und die Nomenklatur der 



Oenof/iera-Bastardierungen. — Ber. d. Deutsch. Bot. Gesellsch. 38. S. 

 166—175. 



4. LoTsy, J. P. 1917. L'Oenothère de Lamarck [Oenothera Lamarckiana de Vkies) 



considérée comme chimère nucléaire. — Arch. Néerland. des Sc. Exact. 

 Ser. HIB, 3, S. 324—350. 



5. —, Kooiman, h. n., Goedewaagen, M. A. .L 1918. De Oenotheren als Kern- 



chimären. — Genetica 1, S. 7—63, 113—129. 



6. Renner, O. 1914. Befruchtung und Embryobildung bei Oenothera Lamarckiana 



und einigen verwandten Arten. — Flora 7, S. 115 — 150. 



7. — 1917. Versuche über die gametische Konstitution der önotheren. — 



Zeitschr. L ind. Abst.- u. Vererb.-lehre 18, S. 121—294. 



8. — 1918. Weitere Vererbungsstudien an önotheren. — Flora //, S. 641 — 667. 



