Periodical Literature 121 



Comparing an open field and the areas covered with brush 

 brings out more fully the influence of the latter treatment: in 

 the field from April to December the evaporation factor was 4.10 

 and 3,80 per cent, at the two depths under the brush 6.70 and 

 6 per cent respectively, showing a considerable influence of the 

 latter treatment, which also reduces weed growth. 



The early thinning under the conditions investigated presents 

 itself as a rational procedure, as well as the leaving of the brush. 



Ungiinstiger Einfluss einer zu grossen Stammzahl auf den Wasserhaushalt 

 geringer Kiefernboden. Zeitschrift fur Forst- und Jagdwesen, April, 1915, 

 pp. 241-8. 



After a lengthy discussion on the pro- 



Aims priety of using the term Zuchtzvahl (for 



of which a good English equivalent seems to 



Seed be lacking) as expressing the selection for 



Selection breeding purposes of seeds from certain 



sites and individuals. Dr. Reuss claims that 



the subject from the forester's point of view was first broached 



and the term used in 1890 by Dr. Cieslar and himself ; that to 



Dr. Cieslar belongs the credit of having in 1887 confirmed Bauer's 



finding that to the heavier seed corresponds a qualitatively better 



development of the plant ; of having recognized the heredity of 



rate of increment; of having, in 1899, recommended the need of 



securing seed from similar site ; of having recognized climatic 



varieties and the need of using seed from climatically similar 



stations ; all of which facts have become basic and generally 



accepted. 



The author himself began careful experiments in the direc- 

 tion of study of heredity in 1879 as regards the influence of the 

 age of the mother tree, using spruce, of 13 to 143 years old, 

 in a series of 15 trial plantations which are still under observation. 

 The result was in favor of seed of medium old and older trees. 

 He then cites findings of Cieslar (1895), according to which the 

 weight of spruce seed generally declines with altitude, while 

 according to Reuss with age of mother tree the weight of seed 

 increases (the younger trees containing also much dead seed), 

 hence the difficulty of judging seed derivation by weight. 



While Engler and Kurdiani consider color of pine seed con- 

 stantly hereditary, Reuss found that in spruce with age of mother 

 tree the seed is darker. He then cites four or five authors dis- 



