56 JOURNAL OF THE [April, 



NOTES ON ENCLOSING IN COLLODION SECTIONS 

 OF OBJECTS EMBEDDED IN PARAFFIN, AND RE- 

 GARDING PROVISORY OBJECT-SUPPORT. 



BY LUDWIG RIEDERER. 

 {Read December tth, 1S89.) 



When working with serial sections for the study of the 

 cellular constitution of animal organs, or for the study of 

 the relative position of the different organs in the body of an 

 animal, the observer often secures a surprising number of sec- 

 tions, usually of large size. As it is possible to inspect these 

 sections only after they are on the slide and finished, the 

 amount of slides and cover-glasses employed, as well as that of 

 time and labor expended is considerable. Consequently only 

 one sectioti out of a smaller or larger number is mounted. It 

 takes some time to finish the slides for inspection, and then it 

 may be found desirable to be able to inspect more of the sections 

 of a certain part of the series. 



How then is it possible to preserve and to keep in order the 

 sections, so that, when needed, the desirable ones can be picked 

 out and be found in good condition ? It will not do to leave 

 sections lying on the paper, where they are first deposited from 

 the knife, even if they are so kept in a box. The slightest cur- 

 rent of air will blow them away, and movement of the box will 

 displace them. Besjdes this, sections not covered by a proper 

 substance will deteriorate by exposure to the air. Many 

 researches have been made, with more or less of success, to 

 .attain the desired end. 



I wish to report to some extent the method worked out by 

 Prof. H. Straper of Freiburg, Baden, Germany, and published 

 in the last number of Zeitschrift filr Wissenscliaftliche Mikros- 

 kopif, Vol. VI. The article is entitled, " About the treatment 

 of sections of objects embedded in paraffin." Three steps are 

 observed in the method : First ; enclosing sections in a film of 

 collodion. Second ; placing them on provisory supports. 

 Third ; handling the sections while enclosed in collodion, in 

 case the object has not already been stained. It is about the 

 first and second steps that I intend to speak, leaving the third 

 for another time. 



