20 



III.— A NEW METHOD OF TEEATING AND MOUNTING 



CELLOIDIN SECTIONS. 



By E. J. Sheppard, F.R.M.S. 



{Bead November 17, 1920.) 



The following observations and description of my work regarding 

 the treatment of " Celloidin Sections " will I feel sure prove of 

 interest to those who have to do section- cutting of tissues which 

 it is necessary to embed in this material. The method so far as 

 I am aware is quite new, and one which introduces " great 

 simplicity " by condensing a branch of micro-technique, at times 

 very tedious and lengtliy, into one wliere such qualities are 

 conspicuous by their absence. 



Owing to the difficulty of removing most of the anilin dyes 

 from celfoidin it is the custom with but few exceptions to stain 

 in toto prior to embedding. 



Probably the best and most simplified method in use at the . 

 present moment for cutting celloidin sections is the so-called 

 " dry-cutting method," fully described in the sixth edition of 

 " Bolles Lee A^ade Mecum." This is doubtless a valuable method, 

 but one requiring a large amount of time apart from that actually 

 taken for the infiltration of the tissue, and possesses the great 

 drawback of the annoying condition known as "frilling" which 

 has to be contended with during manipulation of the sections 

 when cut. 



The method which I shall put before you is not the result of 

 my purposely setting out to discover or devise a new and simplified 

 process, but on the contrary came about hj my endeavour to mount 

 some celloidin sections in " Euparal Media " by adopting the 

 usual procedure that is required for mounting in " Canada 

 Balsam." 



I was somewhat surprised to fiiid that this could not be done, 

 or at least not without some difficulty, which in my endeavour to 

 try and overcome brought about the following highly interesting 

 result. 



Having cut a number of sections by the ordinary " wet method " 

 I cleared a few of these by immersing in " Oil of Thyme." One 

 of these was lifted out of the oil with the aid of a section-lifter 



