1^4: Vererbung, Variation, Mutation. 



Regarding pod number it is considered probable that whether or not a pod 

 is produced from any given node is entirely a matter of environment. There is 

 said to be no reason to believe that the number of pods per vine is in itself in- 

 herited in any degree. Pearl (Orono). 



432) Emerson, B. A., The luheritance of the Ligule and Auricles of 

 Corn Leaves. In: Nebraska Agr. Expt. Stat, 25*^ Ann. Rept., S. 81 — 88, 

 1912. 



The absence of ligule and auricle in the leaves of maize is found to be a 

 recessive character, inherited in typical Mendelian fashion. Pearl (Orono). 



433) Emerson, R. A., The Inheritance of Certain Porms of Chlorophyll 

 Reduction in Corn Leaves. In: Nebraska Agr. Expt. Stat., 25*^ Ann. Rept., 

 S. 89—105, 1912. 



The author presents data from Ins pedigree cultures of maize indicating 

 that albinism (total absence of Chlorophyll) is a recessive character, pure white 

 plants being homozygous recessives. Several different forms of partial Chlorophyll 

 reduction are described for which the details of the mode of inheritance have 

 not been fully worked out. Pearl (Orono). 



434) TrOW, A. H., On the Inheritance of certain characters in the 

 Common Groundsel (Se'necio vulgaris Linn.) and its Segregates. In: 

 Journ. of Genetics, 2, 3, S. 239 — 276, 4 plates, 1912. 



The Common Groundsel, Seneclo vulgaris, is an aggregate species which in- 

 cludes many segregate or elementary species. Twelve of these elementary species 

 from various localities. British and foreign, were cultivated for several genera- 

 tions, and crossed with one another. It is shown that these various elementary 

 species are characterized by varying combinations of about eight factors, for 

 characters in the flow^er, hairiness, stem-colour and leaf-colour. Apparently any 

 desired combination of factors might be made by crossing, so that hundreds of 

 additional "elementary species" might be produced. It was found difficult to get 

 the radiate factor for the flower separately from the very hairy condition of the 

 stem, apparently because the factors for these two characters, which were asso- 

 ciated in one "elementary species", show partial gametic conpling. 



Doncaster (Cambridge). 



435) Toyama, K. (Tokyo, Zool. Inst., College of Agriculture), On certain cha- 

 racteristics of the Silk-Worm which are apparently non-Mendelian. 

 In: Biol. Centralblatt, Bd. 32, Heft 10, S. 593—607, 1912. 



Verf. teilt mit, daß es gelungen ist, auch diejenigen Vererbungserscheinungen 

 bei Seidenraupen, w^elche sich dem Mendel sehen Gesetz zuerst nicht fügen zu 

 wollen schienen, nach näherem Studium restlos dem M ende Ischen Schema unter- 

 zuordnen. 



Eine ganze Reihe von Larven Charakteren waren schon längst als einwands- 

 frei mendelnd bekannt (Anzahl der Häutungen, Blutfarbe, Hautpigmente, gewisse 

 Abzeichen und Parbcharaktere, insgesamt 13 Merkmalspaare). Pur zweifelhafte 

 Mendelfälle gelten bisher die Vererbung der Coconfarbe, gewisse Parb- und Porm- 

 eigentümlichkeiten der Eier und des „Voltinismus" (s. u.). 



Coutagnes und Kellogs Resultate (1902, 1908) über die Coconfarbe er- 

 klären sich durch die Annahme zweier weißer Rassen (V^, w), von denen die eine 

 gegenüber gelb (Y) epistatisch, die andere hypostatisch ist. In den genannten 



