42 JOSHUA ROSETT 



tioii, washed with water and dried, the outer layer bursts and 

 peels off. 



If it is wished to produce tall specimens, a glass tube 8-12 

 mm. is emplo3'ed, and it should be sHghtly inclined, in order to 

 permit the growth to approach the wall and chmb along it. 

 In such cases, too, the fragment of KMn04 (compressed tablets 

 may be used) should be placed at some distance above the 

 bottom of the glass tube. This may be accomplished in the 

 following manner: Previous to filling the tube its wall is mois- 

 tened with the solution at the desired point and the fragment 

 applied. The salt will attach itself to the glass in a few seconds, 

 after which the lower end of the tube is stoppered and the tube 

 is filled. 



Specimens for microscopic study are obtained as follows: 

 Glass microscope shdes are moistened with the solution and the 

 fragment or fragments apphed. The sUdes are then lowered 

 into the solution in a shghtly inchned position, the fragments 

 being attached to their lower surfaces. When growth has taken 

 place to the desired height, the specimens may be prepared in 

 either of three ways. (1) The solution is permitted to dry 

 upon the sUdes. In this case the stems will crack in a number 

 of places, affording a \TLew into their interior. (2) The slides 

 are washed with water and the preparation is mounted in gly- 

 cerinated gelatine. (3) The slides are washed with water and 

 dried, after which the growths are brushed away. In the last 

 case traces of the iimer lining of the stems and of their outer 

 covering adhere to the glass and give a very clear picture of 

 their physical makeup. 



The actual process of growth may be studied in two ways. 

 Specimens may be growTi in a very narrow space, as between a 

 slide and a cover glass, joined by a frame of cardboard or paper. 

 In this case the preparation is placed on the stage of the micro- 

 scope inclined about 10 degrees from the vertical, in order to 

 permit the growth to apply itself to the coyer glass. The other 

 way is as follows: The slide is moistened with the solution and 

 fragments of the salt are strewn upon it. The preparation 

 is then held over a vessel filled wdth water and a few drops of 



