1894.] MICROSCOPICAL JOURNAL 245 



bladder, the rectum and the posterior members, and put 

 the whole till the next day in the fluid used for the in- 

 jection. Remove the distended bladder, slit it ojjen un- 

 der water, and with the internal surface upward brush 

 it until all the epithelium is washed away. Spread it, 

 internal face upward, on a slide, and partly dry it. Stain 

 with hsBmatoxylin and eosin ; mount in balsam. 



Dissociation of Unstriated Tissue. — The foregoing prep- 

 aration will show the muscle cells almost completely iso- 

 lated, as well as cells united in fibres, yet it is important 

 to continue the observation by other methods. 



With curved scissors remove a bit of the muscular 

 layer of the intestine and put it in a drop of the 40 per 

 cent caustic potash solution. In a few minutes disso- 

 ciate with needles ; cover and examine in the potash. 

 This preparation will not keep. 



To make permanent preparations of dissociated muscle 

 cells, proceed thus. With a ligature close a loop of the 

 small intestine of a rabbit, and remove it. Into it inject 

 a 2 per cent solution of ammonia bichromate. When 

 suflBciently distended tie it beyond the syringe, and put 

 it for 1 or 2 days in a bath of the same solution. Wash 

 for 24 hours, after renewing the water. With forceps 

 a shred of the muscular layer is easily torn off. Disso- 

 ciate it in a drop of water on a slide. Stain with picro- 

 carmine in a moist chamber for 12 hours ; mount in 

 glycerine. To observe the nuclei, stain with alum car- 

 mine for 1 or 2 hours instead of with picro-carmine. 



Vessels in unstriated muscles. — From a rabbit whose 

 blood vessels have been injected with Prussian blue, 

 remove a portion of the small intestine and put it in a 2 

 per cent solution of ammonia bichromate. After 1 or 2 

 days' maceration remove by scalpel and forceps as thin a 

 piece as possible from the muscular layer. Wash, stain 

 with hsematoxylin, mount in balsam. 



/Sections of Unstriated, Muscles. — ^Fix an intestinal loop 



