131 



After the sections are cut, they may, if in ribbons, be kept 

 on sheets of paper for some time before fastening to the 

 sh'des, but it is always advisable for fear of accident whereby 

 the sections may become lost or disarranged (disarrange- 

 ment of serial sections is almost as fatal as loss) to fasten 

 them immediately on to the glass mounting slides. 



TREATMENT OF SECTIONS. 



The sequence of treatment. — The sections have first 

 to be arranged AXid fastened on the slide^ and have \ht paraffin 

 removed from them ; then they have to be stained^ and finally 

 cleared and ?nounted. This is the sequence of treatment for 

 sections which have been cut from a specimen not stained 

 in toto. If the specimen has been stained before cutting, the 

 sequence is, (i) arranging and fastening on slide, (2) removal 

 of paraiilin, (3) clearing and mounting. (See also Recapitula- 

 tion, p. 138.) 



In the work of removing paraffin, staining, and clearing 

 it is necessary that the sections fastened on the slide be 

 thoroughly bathed by various fluids. The best way of ac- 

 complishing this is to have the fluids in small glass jars. 

 These jars should be of a diameter slightly greater than the 

 width of the slides used and of a height slightly greater 

 than the length of the slide. They should have closely fit- 

 ting covers to prevent evaporation, and should be heavy 

 and firm enough not to be too easily knocked over. The 

 so-called Naples jars, or the Harvard staining jars, or the 

 Stender dishes of various dealers are of the proper kind. 

 Ten or twelve of these jars containing the various necessary 

 fluids, i.e.^ xylol, absolute alcohol, alcohol of various 

 strengths, staining mixture, clearing mixture, etc., properly 

 labelled, should be arranged on the table in an order corre- 

 sponding to the successive treatment required by the sec- 

 tions. 



