82 



of sand dunes, the growing of wind and fire 

 screens, in planting with and under indigenous 

 pines on the worst class of land, becomes 

 every day more and more apparent and ex- 

 plains the enormous sale of plants in Europe, 

 notwithstanding the incredible dearness of the 

 seed (at present 59s. 3Jd. per pound). A change 

 will come about in a very short time as the 

 Banksian pine begins to yield seed from its 

 sixth year, and thenceforward almost every year, 

 fully-formed seeds which, from my investiga- 

 tions, possess sufficient powers of germination. 

 Boden ' also has published his researches on this 

 subject. From the observations I made which 

 related to examples planted more than 15 years 

 in the forest, consequently the oldest in Ger- 

 many (the seeds of this pine having been 

 collected by Professor Dr. H. Mayr during his 

 first visit to North America in 1885), the follow- 

 ing results were obtained : — 



I litre of the largest cones weighed, fresh, 



552*15 grammes. 

 I litre of the smallest cones weighed, fresh, 



57070 grammes. 

 The average was therefore 561 "42. 



' Samen von Pinus rigida und P. Banksiana. " Z. fiir F. u. 

 Jw.," 1898, p. 17. 



