6. Vererbungslehre. 607 



of 1 BL, 7 Bl, 7 bL, 1 bl. It is noteworthy that the coupling of B with L 

 when introduced frora the sarae parent is on the 7:1:1:7 ratio. 



It is suggested that the terms „coupling" and „repulsion" should be 

 abandoned, since the phenomen on more probably arises by reduplication of 

 cells carrying the factors introduced together. A scheine of anticlinal and 

 periclinal cell-divisions is suggested which might bring about this reduplication. 



Doncaster (Cambridge). 



1672) Payne, F., Drosophila ampelophila Bred in the Dark for 



Sixty-nine Generations. 



(Biological Bulletin 21,5. p. 297—301. 1 fig. 1911.) 



In a previous paper (Biol. Bull. 18,4, 1910), Payne stated the conclusion 

 that flies bred in the dark for 49 generations reacted to light more slowly 

 than those bred in the light, although the darkness had produced no visible 

 effect either in the color of the body or the structure of the eye. He has 

 restested this conclusion on flies bred for 69 generations in the dark, usiug 

 much more precise and elaborate methods, and he now reaches the conclusion 

 „that the darkness operating through a period of sixty-nine generations has 

 produced no visible effect in the reactions of Drosophila to the light of a 

 Welsbach burner. It should be pointed out, however, that the only cave 

 condition present in the experiraent is darkness; that it is possible and indeed 

 probable that factors other than darkness (constant temperature and moisture) 

 may play some part in the changes which have taken place in cave aniraals. 

 If this be true the real test comes not in rearing animals in the darkness 

 but in a true cave environment". Lillie (Chicago). 



1673) Blariiigheni, L., Nouvelles recherches sur la production ex- 

 perimentales d'anomalies keröditaires chez le Mais: I. Reponse 

 ä M. E. Griffon. 



(Bull. Soc. Bot. de France 58,4/5. p. 251—260. 1911.) 

 Polemikartikel. C. L. Gatin (Paris). 



1674) Blaringhem, L., II. Cultures experimentales des anomalies 

 hereditates du Mais de Pensylvanie (Zea Mays pensylvanica 

 Boraf). 



(Bull. Soc. Bot. de France 58,4,5. p. 299—309. 1911.) 



L'auteur maintient, ä la suite de nouvelles experiences, ses conclusions 

 anterieures relatives ä l'heredite des formes anormales de Zea Mays pen- 

 sylvanica obtenues par traumatisme. C. L. Gatin (Paris). 



1675) Cook, O. F., Dimorphie leaves of cotton and allied plants in 

 relation to heredity. 



(Bull. 221, U. S. Dept. Agr. p. 59. figs. 18. pls. 5. 1911.) 



The general thesis of this interesting paper is that the same characters 

 which in certain races behave as Mendelian alternatives in crosses may in 

 related forms show a similar alternative expression of characters in successive 

 internodes of the same individual plant. Attention is first called to the wide 

 ränge of diversity of leaf type in the Malvaceous genera Gossypium, Hibiscus 

 and Abelmoschus, as shown by races of cotton, hemp and okra. The Deccan 

 henip of Egypt (Hibiscus cannabinus) produces two types of leaves, simple 

 and lobed, with an abrupt change from one type to the other. These two 

 types of leaves represent, a segregation of characters between successive inter- 

 nodes of the same plant. These leaf differences correspond to those found in 

 certain races of cotton. Thus the Upland varieties of cotton have usually 



