2iiS Vererbung, Variation, Mutation. 



The writer begins with the assumption, which has now been disproved, fchat 

 Oenofhera lamarcMana is heterozygous and that the mutations result from this 

 heterozygous condition. In his analysis of Capsella he then assumes that all the 

 new forms are really hybrid combinations and merely simulate mutations. In 

 addition to the forms of C. bursa-pastoris described by Shull, the author describes 

 several new ones under the names Selch elliana, Treleascana, arachnoidea, aticnwüa 

 and orhicularis. An interesting and detailed study is made of the various types 

 of leaves which succeed each other in the ontogeny of each rosette. Arachnoidea 

 is a very distinct type with linear leaves. By an analysis of the various forms, 

 in continuation of Shulls work, genetic formulae are assigned to each type 

 with a fair degree of probability, on the basis of factors Controlling various 

 morphological features of leaf development. In this way Setchelliana is considered 

 to be heterozygous for a factor wich is present in duplex in Treleaseana, so that 

 the heterozygotes are distinguishable from the homozygotes, and arachnoidea is 

 homozygous for a new factor (narrow). In this way all the forms can be ex- 

 plained as hybrids of rhomboidea and attenuata, but an explanation of the origin 

 of the latter is not fortheoming. 



Another type, called orhicularis, is more robust with broad leaves. Its off- 

 spring are somewhat variable and the author has not yet deeided whether it is 

 a mutation or a hybrid. Gates. 



806) Engledow, F. L., A case of Repulsion in wheat. In: Proc. Camb. Philosoph. 

 Soc, Bd. XVII, Nr. 5, S. 433—435, 1914. 



In F 2 from the cross Smooth Black x Essex Rough Chaff, evidence was obtained 

 of partial repulsion between the factors for Roughness of Chaff and Black colour of 

 Chaff. The ratio of repulsion is about 1:2.56:2.56:1. Doncaster. 



807) Dexter, J. S., Nabours's breeding-experiments with Grasshop- 

 pers. In: Amer. Naturalist, Bd. 48, Heft 5, S. 317—320, 1914. 



A discussion of Nabours's results in breeding the locusts, Paraiettiex. Nine 

 forms or species differing only in their colour patterns were collected in nature. 

 When crossed, both parental patterns appear in the heterozygote, there is no 

 dominance. Each pattern was allelomorphic to any other, with one exception. 

 The writer points out that there appear to be eight distinct allelomorphs, and 

 any gamete will only contain one of them while any zygote will contain only two. 



There is an exception, however, for which a "cross-over" explanation is sug- 

 gested. In this case a CE male was mated to a BI female and one BEI indi- 

 vidual appeared. Gates. 



<S08) Sturtevant, S.H., Linkage in the silkworm moth. In: Amer. Natura- 

 list, Bd. 48, Heft 5, S. 315—317, 1914. 



Short discussion of results of Tanaka on linkage in silkworms (Journ. Coli. 

 Agr., Tokyo 1913), and comparison with results of Baur, Morgan, Punnett and 

 others, with regard to the nature of the inheritance of various sex-linked characters. 



Gates. 



809) Carpenter, G. D. H., The Inheritance of small variations in the pattern of 

 Papilio dardanus. In: Trans. Entoin. Soc. London, Bd. 11)13, Heft IV, S. 656—666, 

 2 pl., 1914. 



It is shown that the size of a small white spot is quite clearly inherited. 



Doncaster. 



810) Surface, F. M., A Pedigree System for Use in Breeding Guinea 

 Pigs and Rabbits. In: Ann. Rept. Maine Agr.Expt. Sta., S. 306— 313, 1913. 



