— 143— 



ous system, of an entire eye, or tissues or orirans con- 

 taining much fibrous tissue. It may be used whenever not 

 very tliin sections (less tlian 10 ,". to 15 ,".) are required. 

 Tiie cclloidiu or collodiuni need not be removed l)efore 

 stnining or mounting; and unless the aniline dyes are used 

 for coloring, very little stain is taken by the celloidin. The 

 sections need to be cleared in oil of bcrganiot, as tlu; oil of 

 cloves dissolves the celloidin. The following nnihod for 

 staining and mounting celloidin sections in series, is recom- 

 mended l»y Weigert : — * 



(1) A clean glass plate is covered with n thin hiycr of 

 a solution of collodiuni; this is to be spread out as cvcndy 

 as possible over the entire surface. The i)late is now 

 placed on edge, and the collodiuni allowed to dry, care 

 being taken to keep the dust from it. 



(2) A section is placed on a strip of "closet paper," 

 near one end. Succeeding sections, as soon as cut, are 

 placed to the right of it. They are removed from the 

 knife to the strip of paper, by holding the pajjcr extended 

 under the knife, and slipping the section onto it. To keep 

 the sections from drying, the strip of paper is, after the 

 removal of every section, placed in a flat dish, in which 

 several layers of filter paper, have been spread out and 

 thoroughly saturated with 80% alcohol. On each strip of 

 paper is arranged only one row of sections; the strips are 

 kept in the dish in the order used. 



(8) As soon as a number of strips have been covered 

 with sections, they are arranged, sections downward, on 

 the layer of collodium above described, and gently pressed 

 to it. The strips of the papei can now be removed, the 

 sections adhering to the layer of collodium. Several layers 

 of filter paper are now pressed over the sections, in this 

 way removing as much of the alcohol as possible. 



(4) Before the sections have time to dry a layer of 

 the collodium solution is poured over them, equally dis- 

 tributed, and allowed to dry. As soon as dry the plate 

 may be placed into 80% alcohol, where it may be kept, or 



*Takeii from Rawitz Leitfadeu der histologischeu Uutersuch- 

 ungen. Page 37. 



