554 



EXPERIMENT STATION RECORD. 



seeds takes place withiu the stratum of air tbat lies about 30 or 40 ft. 

 from the earth's surface. The desirability of investigations as to ver- 

 tical distribution is pointed out. 



An investigation of various germination media. B. Jonsson 

 (Report Lund Seed-Control Slat ion for 1897, pp. 7-12, 28,29).— The gen- 

 eral practice adopted in Scandinavian seed-control stations is to ger- 

 minate the seed between pieces of moist paper or cloth. Tbe medium 

 in which the seed is placed differs greatly among the Swedish stations. 

 The author collected over 30 different kinds of paper or cloth used for 

 this purpose in Swedish stations, and subjected them to a critical exam- 

 ination. A number of samples were tested to study which kinds were 

 especially adapted for the purpose in view, and determinations made of 

 weight, ash content, porosity, hygroscopicity, and rapidity of evapora- 

 tion from the surface of the paper or cloth. The samples examined 

 were grouped as filter paper, blotting paper, brown paper, felt, mole- 

 skin, and linen. The following table shows the average data obtained 

 for these groups of media : 



Examination of germination media. 



Medium. 



Filter paper (white) 



Blotting paper (white or col 



ored) 



Brown paper 



Felt 



Moleskin 



Linen 



Number 



of 

 samples. 



Weight 

 of 19.76 

 sq. cm. 



Grams. 

 0.17 



.37 



.25 



.70 



1.02 



Ash 

 content. 



Per cent. 

 0.46 



a . 47 

 2.06 



Height 

 to which 



water 

 rose, dur- 

 ing 3 min. 



Mm. 

 2.90 



31.0 

 13.0 

 3.5 

 68.0 

 21.0 



Amount 

 of mois- 

 ture 

 taken up 

 in satu- 

 rated al 



Evaporation during 

 4 hours — 



Per 



mosphere TO " f 

 during24 lll6(lwU1 ' 

 hours. 



Per cent. 

 25.5 



16.0 

 24.0 

 19.5 

 11.9 



Grams. 

 2. 695 



1.806 

 1.777 

 .483 

 .315 



Per same 



surface 



(19.76 sq. 



cm.). 



Per cent. 

 69.0 



62.0 



58.5 



9.0 



11.0 



62.5 



a Average for 6 samples. 



In order to be adapted for use in germination tests, the paper should 

 be pure, free from injurious components or coloring matter, and as far 

 as possible free from fungi and bacteria. It should therefore be kept 

 and handled carefully, and preferably sterilized. It should be soft 

 and pliable and of good keeping quality. Its ash content should be 

 as low as possible, since a high ash makes the paper hard, and may 

 interfere with the germination by the ash components being dissolved 

 in the water of the germination bed. Porosity is essential, to permit of 

 circulation of air; for this reason heavily sized paper is objectionable. 

 In the author's opinion a paper fulfilling the preceding demands is 

 preferable to either clay or terracotta dishes, sand, or soil beds. — F. 



W. WOLL. 



Report of Swedish seed-control stations for 1896 {Meddel. K. 

 Landtbr. Styr., 1897, No. 42, pp. 314-382). — The report includes the aver- 

 age data, with extremes, of 9,913 seed analyses made at the 18 Swedish 



