68 



Varietäten, Descendenz, Hybriden. 



the stages by which he arrived at the conclusion that anthocyans 

 are reduction products of flavone or flavonol Compounds. Reference 

 is made to criticism of Wheldale and Basse tt and of Will- 

 stätter and his collaborators: and to the later paper in which the 

 latter withdraw their criticism that the pigment resulting from the 

 reduction of quercetin is not identical with the anthocyan pigment 

 cyanidin obtained from cornflower. 



The author summarizes the chemical work that has been accom- 

 plished thus far: 



1) Anthocyanin pigments, whose structures have been definitely 

 established, have been isolated in a chemically pure and crystalline 

 condition from the following plants: cornflower and rose (cyanin), 

 cranberry (monosaccharide of cyanidin), Pelargonimn zonale (pelar- 

 gonin), deep coloured grapes (eonin), Delphinium (delphinin), bilberry 

 (myrtillin), and two types of holly hock. 



2) Chemical evidence has now established the facts: 



a) that the anthocyans always occur as glucosides, 



b) that the same pigment may be capable of showing a blue» 

 purple or red colour according as it exists as an alkali salt, free 

 pigment, or oxonium salt of some acid. All anthocyans do not 

 however form blue alkali salts, 



c) that the anthocyans may be obtained from flavonols by 

 reduction followed by spontaneous dehydration, 



d) that glucosides of flavonols can pass by reduction to gluco- 

 side anthoc5rans (i. e. anthocyanins) without intermediate hydrolysis, 



e) that. from analytical evidence, the molecular weights of the 

 anthocyanidins (hydrolysed non-glucoside pigments) are of the same 

 Order as those of the flavonols. W. Neilson Jones. 



Gregory, R. P,, Note on the inheritanceofheterostylism 

 in Pyintuld acaulis Jacq. (Journ. of Genetics. IV. p. 303—304. 

 1915.) 



The results of the experiments on the wild primrose here 

 recorded agree with those obtained in the case o{ Primula shiensis: 

 i.e. the inheritance of the characters of short and long style is of a 

 simple Mendelian type, the short style being dominant. All the 

 short styled wild plants, nine in number, were apparently hetero- 

 zygous. 



The results of crossings may be shown in tabular form as 

 foMows: 



W. Neilson Jones. 



Wheldale, M., Our present knowledgeofthechemistryof 

 the mendelian factors for flower colour. II. (Journ. of 

 Genetics. IL p. 369—376. 1915.) 



The author first of all gives a summary of Willstätter's 



