PERIODICAL LITERATURE. 

 BOTANY AND ZOOLOGY. 



An interesting, although not yet completed, 



Self series of experiments in self-fertilization of 



Fertilisation. pine and spruce is reported by Nils Sylven. 



The method pursued is the usual one of 



isolating fruitbuds by means of paper bags. On the pines, the 



cones were poorly developed (perhaps on account of improper 



tieing with iron wire) ; the cones did not open, and the seeds 



were all imperfect and non-germinative. 



In spruce, the isolated branches having been twice shaken to 

 assist poUinization, four out of five trees developed good cones 

 and contained good germinative seeds so far as not destroyed 

 by the gall wasp; but with the exception the germinating per 

 cent, was lower than that from open branches. Of one of the 

 trees, however, 72 plants were grown from self-poUinized seed, 

 36 or 33 1/3% having died during the summer, while only 9.9% 

 of plants from other seed were lost ; the surviving plants of either 

 derivation being equally vigorous. 



It is pointed out, that while self-fertilization depresses the 

 germinating per cent., the growing of special favorable races, 

 e. g. the green-coned, late-budding spruce, will only be accom- 

 plished by this means. This consideration lends practical value 

 to this kind of inquiry. 



Uebcr Bestdiibungsversuche mit Kiefcr und Fichte. Mitteilungen 

 aus der forstlichen Versuchsanstalt Schwedens. Heft 7, 191 1. 



Interesting observations, continued for 15 

 Phenology years on the influences which determine the 



of flowering of plants in the neighborhood of 



Flowering. Brussels are reported by Vanderlinden. 



The greatest variation in the date of 

 flowering is observed in the very early and the very late flower- 

 ing plants, while the amplitude of those flowering in May is 

 very small. The reason is, that with all early flowering plants 



