346 MUSCLE AND TENDON (NERVE-ENDINGS). 



of Wagner. The terminal arborescence may be impregnated with 

 silver. A portion of the surface of the organ is rubbed with lunar 

 caustic until it appears opaque, then removed and the plates teased 

 out in water. This gives negative images. 



Or, electric plates, isolated by teasing after twenty-four hours in 

 osmic acid as above, and kept for some days in one-third alcohol, 

 are washed and placed on a slide with their ventral surface upper- 

 most. They are then treated with a few drops of 0-5 per cent, 

 solution of chloride of gold and potassium, and those which become 

 violet are washed and mounted in glycerin. This gives positive 

 images. 



These may also be obtained by putting material fixed by osmic 

 acid into 2 per cent, solution of bichromate of ammonia for a few 

 weeks, then teasing, staining with alum hsematoxylin, and mounting 

 in damar. 



Torpedo. BALLOWITZ (Arch. mik. Anat., xlii, 1893, p. 460) gets 

 the best results by the rapid Golgi impregnation. 



An electric column, with about \ to 1 centimetre of tissue round 

 it, is dissected out, and put for three to four days into the osmium 

 bichromate mixture ; then for one to three days into f per cent, 

 silver, cut without imbedding and mounted in xylol balsam. Im- 

 pregnates all the important elements. See further, on the whole 

 subject, BALLOWITZ, Encycl. mik. Techn., 1910, p. 298. 



CAVALIE (Bibl. Anat., xiii, 1904, p. 214) takes material fixed 

 with osmic acid of 2 per cent, and impregnates it with gold by the 

 method of NABIAS, and mounts in glycerin. 



Raja. IWANZOFF (Bull. Soc. Nat. Moscou, ix, 1895, p. 74) fixes 

 the organ in the tail of Raja with liquid of Flemming, stains with 

 haemacalcium and eosin, and makes paraffin sections. 



BALLOWITZ (Anat. Hefte, 1 Abth., vii, 1897, p. 285) finds the 

 method of Golgi excellent for this organ. He also makes sections 

 after fixing in saturated solution of sublimate (in sea- water), or in 

 liquid of Flemming, and examines them in water. Methylen blue 

 may be used, intra vitam. Gold is little good. 



Gymnotus. BALLOWITZ (Encycl. mik. Technik., p.' 303) fixes with 

 Flemming, and makes sections. He also commends impregnation 

 with gold chloride, but not the Golgi method. 



Malapterurus. BALLOWITZ (ibid., p. 202) fixes with picro-subli- 

 mate, with Flemming, or with various mixtures of bichromate, 

 sublimate, and formol, and uses gold chloride and Golgi impregna- 

 tions. He macerates in liquid of Miiller or saturated aqueous 

 solution of picric acid. 



