26 



BO TANICAL MICRO TECHNIQ L V: . 



ing fluid, and the slides are placed in it so that the sides 

 bearing the sections are turned outward. Any injury to or 

 scraping off of the sections is thus prevented. It is best not 

 to fasten the dishes together, but simply to place them inside 

 of each other and to load the inner one with shot or other 

 weight, to prevent their being floated by the fluid in the 

 outer dish. In order to distinguish the different objects in 

 the apparatus from each other, we may use crystallizing 



FIG. 13. Apparatus for staining microtome sections. 



dishes provided with lips for pouring. If then the appa- 

 ratus is always filled in regular sequence in the same direc- 

 tion from this lip, it is only necessary to note the numerical 

 positions of the separate preparations. 



38. For further details the reader is referred to the de- 

 scription of individual methods. Here it may be said that 

 preparations are rarely to be studied in the condition in 

 which they are taken from the staining fluid. Often very 

 useful effects are obtained by first strongly "overstating" 

 the preparations and then washing them in water, alcohol, 

 dilute acid, or the like, until only certain parts of the cell 

 contents appear colored. In many cases the treatment of 



