354 MUSCLE AND TENDON. 



(3) The same process, with omission of the preliminary acidification, is to 

 be recommended for cold-blooded animals. 



(4) The method of GOLGI (Mem. delle R. Accad. di Sci. di Torino, ii, 

 32) is applicable to all classes of objects. It is as follows : Acidification 

 with 0'5 per cent, arsenic acid, impregnation in 0*5 per cent, solution of 

 double chloride of gold and potassium, and reduction in 1 per cent, arsenic 

 acid in sunlight. 



(5) A modification of the last (apparently due to MATS) consisting in im- 

 pregnation in a mixture containing 0*5 per cent, arsenic acid, O25 per cent, 

 chloride of gold and potassium, and O'l per cent, osmium, and reduction as 

 before, is stated to be particularly applicable to Reptilia. (This process has 

 been further modified by MARSHALL [Quart. Journ. Mic. Sci., 1890, p. 73 ; 

 Journ. Roy. Mic. Soc., 1890, p. 404], who impregnates [after previous im- 

 mersion for a few seconds in 1 per cent, acetic acid] in a mixture of 20 parts 



1 per cent, acetic acid, 4 parts 1 per cent, gold chloride, and 1 part 1 per 

 cent, osmic acid. He had found that the arsenic acid of Mays' formula dis- 

 integrated the muscle-fibre.) 



Kiihne also remarks that teasing ought to be done in the gold solution. 

 Specimens should be removed from the gold every few minutes, and from 

 the reducing medium every hour, so that the right duration both of impreg- 

 nation and reduction may be hit off. Preliminary acidification is unfavor- 

 able to the preservation of the arborescence, and the treatment with acids 

 after impregnation is best abbreviated as much as possible. Mounting in 

 formic acid glycerin is not favorable for the preservation of detail. This 

 is best studied in arsenic acid. Entire muscles are best mounted in balsam. 



See also an older method of MAYS in Zeit.f. Biol, 1884, p. 449 ; Zeit. /. 

 wiss. Mik., 1885, p. 242. 



Tendon. 



671. Corpuscles of Golgi (RANVIER, Traite, p. 929). Take 

 the tendon of the anterior and superior insertion of the gemini 

 muscles of the rabbit. Free it as far as possible from adherent 

 muscle-fibres. Treat it according to the formic acid and gold 

 method ( 225), and after reduction of the gold scrape the 

 tendon with a fine scalpel, in order to remove the muscle-fibres 

 that mask the " musculo-tendinous organs." 



672. Corpuscles of Golgi (in the tendons of the motores 

 bulbi oculi) (v. MARCHI'S methods, Archivio per le Scienze 

 Mediche, vol. v, No. 15). The enucleated eyes, together with 

 their muscles, were put for not less than three days into 



2 per cent, bichromate of potash. The muscles and tendons 

 were then carefully dissected out, stained with gold chloride 

 and osmic acid (Golgi' s method, supra, 670), and by the 

 methods of MANFREDI, given in 228. 



Mount all these preparations in glycerin (balsam clears too 



