350 Palaeontologie. — Agricultur, Horticultur und Forstbotanik. 



aber in Wirklichkeit nicht eine Frucht, sondern ein isolirtes 

 Polster einer Sigillaria ist, die zu derselben Formreihe gehört, 

 Avie Sigillaria Defrancei Brongniart. Als Ursache dieses so 

 ärgerlichen Versehens ist die unrichtige Aufstellung des Objects 

 und der Umstand zu betrachten, dass die Möglichkeit der bei 

 Lepidodendron häufig vorkommenden Erhaltung eines isolirten 

 Blattpolsters bei einer Sigillaria übersehen wurde. Auf Grund 

 der Entdeckung solcher Formen, wie Plaglozamites Planchardi 

 Renault sp., das sowohl in der obercarbonischen Flora (Cala- 

 modendron-Stiüe), als auch in der permischen bekannt ist, und 

 Lepidodendron ociilus felis Abbado sp., das bisher nur in der 

 Provinz Schansi in Nord -China in Ablagerungen gefunden 

 worden ist, die Prof. R. Z ei Her zum Permocarbon rechnet, 

 gelangt der Autor zu dem Schlüsse, dass die Ablagerungen 

 des janta i-R e vi er s, die jene Pflanzenreste beherbergen, 

 wahrscheinlich als Uebergänge zwischen den obencarbonischen 

 und den permischen aufzufassen sind. Zum Schluss bringt 

 der Verf. Vermuthungen in Betreff der das Jantai-Revier 

 umgebenden Kohlenfelder der südlichen Mandschurei vor, 

 denken er das nämliche Alter zuschreibt, wie jenen. 



M. Zaiessky. 



Wood, T. B., and R. A. Berry, Variation in the chemical 

 com Position ofMangJes. (Journal of Agricultural Science. 

 Vol. I. 1905. p. 176) ■ 



The following summary concludes the paper: 



„That the most convenient method of sampling roots for analysis is 

 to remove a core from each root, and that when using this method at 

 least 50 roots must be cored in order to obtain a sample representing 

 the composition of the bulk of roots grown on a field. 



That a large proportion of the commonly grown strains of mangles 

 may be assigned to one or other of five types. 



That of these types, four have their cropping power and percentage 

 of dry matter so nearly in inverse proportion that they yield practicaily 

 the same weight of dry matter per acre. 



That the fifth type, Long Red, yields considerably more dry matter 

 per acre than the other four varieties. 



That large roots on the average contain more water and less dry 

 matter than smaller ones. 



That theie is a considerable Variation in the composition of mangles 

 from year to year, probably depending upon such conditions as rainfall 

 and sunshine at particular periods of growth. 



That manurial treatment causes distinct variations in composition 

 the most noticeable point being that excessive applications of nitrogen 

 delay ripening and decrease the percentage of dry matter. 



That different farms grow roots of different composition. 



That there is very great Variation between individual roots of the 

 same variety grown side by side, in content of dry matter, sugar, and 

 nitrogen, and in size, shape, and colour; in fact in all the characters 

 which we have been able to observe. 



That there is so little correlation between the different characters 

 that it is possible to pick out for seed-mothers large roots containing 

 high percentages of dry matter rieh in any desired constituent, and it is 

 suggested that, from analogy with the sugar beet, continuous selection 

 carried out in this way may result in improvement in any desired di- 

 rection. 



