6. Vererbungslehre. 301 



■s 



831) Blaringhem, L., Le röle des traumatismes dans la production 

 des anomalies hereditaires. 



(Coinpt. Rend. Acad. des Sc. de Paris 152,23. p. 1609—1611. 1911.) 

 L'auteur, dans cette note de polemique, declare qua l'aide de mutilations 

 il produit plus commodement des varietes qui se produiraient d'elles meines 

 dans la nature, et qui sont hereditaires. C. L. Gatin (Paris). 



832) Wkeldale, M. (Newnham College, Cambridge), On the formation 

 of Anthocyanin. 



(Journal of Genetics 1,2. p. 133—158. 1911.) 

 The authoress, after discussing the results obtained by previous observers, 

 approaches the question of Anthocyanin formation from various directions. 

 1. She shows that analogous reactions suggest that if anthocyanin is formed 

 by the oxidation of a chromogen, the formation of this chromogen may by a 

 reversible reaction, brought about by an enzyme, between water and a gluco- 

 side — glucoside + water ^t chromogen -)- sugar. A number of analogous reac- 

 tions are quoted. 2. The distribution of anthocyanin in plants under normal 

 and abnormal conditions is discussed, for comparison with 3. the concentration 

 of glucosides and sugars in various tissues. The facts recorded under 2. and 

 3. show that there is a relationship between pigmentation with anthocyanin 

 and assimilation, and that concentration of glucoside is aecompanied by in- 

 crease of anthocyanin. 4. Evidence is given of the widespread oecurrence of 

 glucoside-splitting enzymes; the nature of the oxidising enzyme is more doubtful. 

 5. Experiments with feeding with sugar show as a rule that the production 

 of anthocyanin varies inversely with the power of turning the sugar into 

 starch. These facts lead to the conclusion that anthoeyanins are oxidation 

 produets of a chromogen (aromatic) which is formed from a glucoside by a 

 reversible reaction due to an enzyme. Their local formation depends on 

 differences of concentration of either sugars or glucosides. The various heri- 

 table types of colour are due to the presence in different forms of different 

 enzymes; these are classifiable into two chief groups, a) these in which loss 

 of an enzyme causes increase in colour, in which case the coloured form 

 may by recessive to the type; b) these in which loss causes decrease in 

 colour, when the less coloured are recessive to the deeper coloured. 



Doncaster (Cambridge). 



833) Granier, J. et L. Boule, Sur le caractere heterogamique des 

 gemini chez Impatiens glanduligera Royle. 



(Compt. Eend. Acad. des Sc. de Paris 152,15. p. 1020—1022. 1911.) 

 Les auteurs ont recherche si les chromosomes qui se conjuguent en gemini 



se groupent ainsi au hasard, ou si leur groupement se fait avec selection, de 



maniere ä accoupler des chromosomes porteurs de caracteres particuliers, comme 



on l'a dejä observe chez les Insectes. 



L'Endymion nutans n'a fourni aux auteurs sur ce point, aueune indi- 



cation. Par contre, chez Impatiens glanduligera les cellules somatiques 



possedent toutes deux chromosomes de grande taille. 



Ces deux macrochromosomes fönt place ä un seul dans les cellules repro- 



duetrices mäles. II en existe un autre dans la cellule reproduetrice femelle de 



sorte que la cellule ceuf contient ä son tour, deux macrochromosomes. 



C. L. Gatin (Paris). 



834) Haack, W., Die Beschaffung des Kiefern- und Fichten- 

 samens einst, jetzt und künftig. Arbeiten aus dem mykologischen 

 Laboratorium der Forstakademie Eberswalde. 



(Mitteilungen d. Deutschen Forstvereins. No. 6. 1909.) 



