52 METHODS OP MICROSCOPICAL RESEARCH. 



immerse costal cartilage of a kitten, puppy, or 

 young rabbit, rat or guinea pig, for twelve hours ; 

 a piece of the sciatic nerve of the frog for ten 

 minutes ; the non-medullated nerve running in the 

 wall of the splenic vein of an ox, also a piece of 

 human placenta. A 1 per cent, solution may be 

 injected into a testis with a hypodermic syringe, 

 and the whole organ may then be placed in alcohol. 

 The following are best treated with a -J- per cent, 

 solution, namely : liver cells of a dog or small 

 animal (the liver is cut across and the cut surface 

 scraped) are placed in the solution for an hour. 

 Areolar tissue is demonstrated by injecting a -J- 

 per cent, solution into the groin of a puppy or 

 kitten immediately after death. A bulla is thus 

 formed, which must be snipped out with scissors, 

 spread on a slide stained with logwood and then 

 covered. A per cent, solution may be forcibly 

 injected into the anterior horn of a fresh spinal 

 cord. The part is cut out, macerated for two days 

 in dilute alcohol, and the multipolar cells isolated 

 by " teasing," after staining with picro-carmine. 

 A J per cent, solution (the strength most 

 frequently employed) may be used for showing 

 mucous tissue ; thus : inject the axilla, or groin, 

 of a very young embryo, as described above. 

 Pieces the size of a pea of the following may be 

 hardened in a J per cent, solution : Submaxillary 

 gland, fresh pancreas, pieces from each end of 

 the stomach, small intestines, supra-renal cap- 

 sules of the horse, human skin. Place a piece of 

 the anterior horn of a fresh spinal cord for ten 

 days in a ifeth per cent, solution, then, after washing 

 away the greyish deposit, place it in an equal 



