252 Pflahzenchemie. — Angewandte Botanik. 



cember, Misaki, 0.155; January, Misaki, 0.178; March, Misaki, 0.202; 

 May, Enoshima, 0.202; and June, Enoshima, 0.348. 



Generally, algae in an open sea seem to contain more iodine 

 than the sarae species in an inland sea. The iodine content of the 

 samples obtained in March at Misaki (open sea) was nearly equaJ 

 to those obtained in May at Enoshima (inland sea). 



In dead algae, the largest part of their iodine easily diffuses in 

 sea or fresh water, therefore drifted algae are not suitable for the 

 preparation of iodine. M. J. Sirks (Wageningen). 



Lamb, W. H., Value of the contest. (Journ. of Heredity. VI. 

 p. 424—428. 1915.) 



In this paper an appeal for the preservation of gigantic trees is 

 made, not solely in the name of science, but also for their grandeur, 

 Utility and beauty, which present an appeal not equalled by the 

 interests of any scientific investigation. These giants should be 

 protected in every possible manner by their present owners whom 

 they are destined to outlive, and legal provisions should be made 

 to prevent their destruction by future owners of the land. 



Especially large individuals of white elm {ülmus americanä), 

 v/hite oak {Qtiercus alba), Sycamore {Platanus occidentalis), Chestnut 

 Castanea dentata), black walnut {Juglans nigra) and yellow poplar 

 Liriodendron tulipifera) are of great importance ; the sycamore is 

 the largest hardwood tree; one individual at Worthington (Ind.) 

 reaching 42^/4 ft. in circumference. Distribution of these large trees 

 in North-America is shown in six maps; dots represent in these 

 maps location of the best specimens submitted in the contest. 



M. J. Sirks (Wageningen). 



Macoun, W.'T.» Plant breeding in Canada. (Journ. of Here- 

 dity. VI. p. 398-403. 1915.) 



The writer describes in his paper in details the work in bree- 

 ding with apples, hitherto done in Canada, begun by the late 

 Dr. W. Saunders. But also work with other fruits has been men- 

 tioned: pears, plums, cherries, grapes, gooseberries, strawberries; 

 selections for earliness in vegetables have been made with tomatoes, 

 beans, peas and corn particularly. Comparatively little work has 

 been done in breeding ornamental plants, but some progress has 

 been made with roses, sweet peas, geraniums, petunias and colum- 

 bine. Some interesting and attractive Fg-seedlings are growing from 

 a cross made between Berberis thunbergi'i and B. vulgaris piirpurea. 



M. J. Sirks (Wageningen). 



Nilsson-Ehle, H„ Svalöfs Klockhafre III. Ny, särdeles 

 bögt afkastande, Tidig sort för mellersta Sveriges 

 svarthafreomräd e. [Svalöfs Glockenhafer III. Neue, 

 sehr ertragreiche, frühe Sorte für das mittelschwe- 

 dische Schwarzhafergebiet]. (Sveriges Utsädesf. Tidskr. 

 XXVI. p. 219-231. 2 Tafeln. 1916.) 



Die vom schwedischen Saatzuchtverein vorgenommene Züch- 

 tung von Schwarzhafersorten für Mittelschweden ist in ver- 

 schiedenen Richtungen betrieben wurden. 



Durch Auswahl aus dem alten schwarzen Landhafer ging als 

 erstes Resultat der Tyrishafer hervor. Die mittelschwedischen 



