Seed Testing 275 



a short distance below the upper edge. The glass strips are put 

 close together so as to allow the wick attached to the 8 centimeter 

 woolen disc placed on the glass to run down into the water. 

 Above the woolen disc, which is made from all wool blanketing, 

 is placed a coarsely knitted disc made out of loose yarn, and 

 above this again is a circular filter paper upon which the seed to 

 be germinated rests. The three different discs and the seed are then 

 covered by a glass bell jar provided with a hole near the apex 

 to allow entrance of air. For the same reason the filter paper, 

 knitted disc and woolen cloth have a hole near the center. The 

 water in the tank which is heated by means of a Bunsen gas 

 burner is made to circulate by placing a metal plate resting upon 

 metal supports about two inches above the tank bottom. The 

 temperature of the water is allowed to vary from 15 to 25 degrees 

 centigrade. This apparatus is easy to operate, occupies re- 

 latively small space for the number of tests and insures uniform 

 results of high standard. 



Though the main work of the Seed Control Station centers 

 around seed used in agricultural practice, the later years have 

 witnessed a steady increase in the number of forest seeds sub- 

 mitted for testing. The work in this field extends over a much 

 shorter period so that the desired standards for all species have 

 not in all cases been perfected, but most of the tests are run from 

 21 to 28 days, though in one instance the seed of one species of 

 Rhus germinated only one seed in one year, while the remain- 

 ing seeds were in perfect condition. 



The articles published by the Station staff, principally by the 

 Director, are very numerous and cover the field well in respect 

 to peculiarities of different kinds of seed and the methods of 

 overcoming them, the diflficulties experienced in testing, identify- 

 ing the seed, and the regulation of the seed market. Some of 

 the articles which may prove of interest to investigators are listed 

 below : 



REFERENCES 



Tests of Forest Seed, 1902-1907, Dansk Tidsskrift for Skov- 



vasen, Volume XX; Danish Seed Control Station, 1896-1907, by 



K. Dorph-Petersen, published by J. Jorgensen and Company, 



Copenhagen; Analysis of Forest Seed for 25 years,^ (not for 



'Reviewed in F. Q., volume XIII, p. 527. 



