Staining Blood and Epithelium, etc. 155 



medium or glycerine jelly. In this specimen only the 

 interstitial cement substance will be seen. To compare 

 with it, cut out a similar piece, wash it in distilled water, 

 and stain it with hsematoxylin for ten minutes ; wash away 

 all excess of stain with distilled water, and mount in 

 Farrant's medium or glycerine jelly. In this specimen the 

 nuclei will be seen stained blue. Specimens of mesentery 

 showing endothelium may also be mounted in Canada 

 balsam. When this is desired, stain the tissue as directed 

 above, dehydrate in methylated spirit, clear in clove-oil, and 

 mount in Canada balsam. 



Teasing-out Tissues. — Take a very small piece of the 

 tissue, place it on a slide in a few drops of distilled water, 

 and with a couple of needles mounted in holders carefully 

 separate the fibres from each other. When the parts are 

 sufficiently isolated, drain away the water, add a few drops 

 of the mounting fluid, and apply the cover-glass. When 

 teasing it is very important that a proper background should 

 be used, so that the object may be easily seen. For a 

 coloured specimen, a piece of white paper should be used, 

 and a transparent white tissue will be seen better on a dark 

 ground, such as a piece of black paper or American cloth ; 

 the slide should be examined from time to time under the 

 low power of the microscope to ascertain when the tissue 

 is teased out enough. 



White Fibrous Tissue. — Harden some tendons from a rat's 

 tail in methylated spirit for a week. Then soak a small 

 piece in water to remove all trace of spirit, place it on a 

 slide in a few drops of water, and tease it up until the fibres 

 are separated from each other. Drain away the water, add 

 some Farrant's medium or glycerine jelly, and apply a 

 cover-glass. 



Yellow Elastic Tissue. — Place small pieces of the liga- 

 mentum nuchse of an ox in chromic acid and spirit for ten 

 days. Then proceed as above. 



Striped or Voluntary Muscle. — Harden small pieces of 

 muscle of a pig in a 2 per cent, solution of bichromate of 



