GEBMIXATION. 177 



and covered with i c. m. of earth, so that the sprout- 

 ing is done in a medium, of i c. c. m. The. surface is 

 then sprayed with water. The natural advantage of this 

 arrangement is, that the counting of seed offers no dif- 

 ficuhy. During the interval of 14 days the seed should 

 be watered three times with an atomizer, it being 

 very important that the soil be not too moist during 

 the test. 



The use of a porous terra-cotta plaque, with several 

 parallel openings in the bottom to keep the seed in 

 position, may, for some practical purposes, give satis- 

 factory results; the moisture requisite is absorbed by 

 the terra-cotta from the water in which this plaque is 

 placed. Many of the existing germinators are earthen- 

 ware; respecting their use, it is considered important 

 not to use them for a second time, as organic sub- 

 stances collect in the pores of the material, which soon 

 become centres of infection; as a result, the seed, 

 instead of germinating, will simply rot. While by 

 heating the terra-cotta plaque it is possible to destroy 

 all germs, the porosity of the receptacle would soon 

 disappear and it would become worthless for the 

 purpose intended. 



The Marek germinator consists simply of earthen 

 plates about eight inches in diameter, and one to two 

 inches in depth; they are filled with fine sand combined 

 with 5 per cent, of muddy substance. The surface is 

 moistened, and compressed to one-third of an inch with 

 A special instrument. The surface is divided into 

 regular intervals in two directions, and at the point of 

 intersection the seeds are placed, their number being 

 counted, and then covered with sand falling from a 

 sieve. All sand above the outer border of the plates 

 is removed by running a ruler over its surface; the 

 depth of covering above seed is about one-third of an 

 inch. Great care should be taken to keep moisture 

 within reasonable bounds. The seeds and sprouts 

 12 



