The ri'laliims of init()c|i(,inlri.i .iml hIIki- cyfopl.-tsini«- (•«mslifm-iits ftr-. 4^1 



lil'st illlldiliiccd ;is ;i \il;il >l;iiii hy M iilim-lis (IK'.)'), p. .■)(').").. Hi- 

 ;i|»|)li('(l it tu glaiiil ccllv ;(> ,1 iiic;iii> (i| dciin iii>t i;i I iirj Hit- l)a>al lila- 

 iiiciits. Since then il has iir\ri' Itccn r.\ltii>i\ civ iimmI. litMisIcy (IDI 1 ) 

 lias slidwii llial it is almost sitpcilic ln|- inildclMiiMlria ami lia> iilili/j-d 

 it as such. In liu'. IS a spinal üani^licn ci'll is illiisti-att'd which was 

 stained by injection with, and subsequent immcisioii in. a 1 : 10000 

 solution of janus green in O.Iò^Jq sodium rhlmiili' xdiiiinii. The vast 

 wealtli of mitochondria as compared wiih the nilifi' lii:uic> i> of 

 course due to two factors: first, tliat we an; dcalinL: with an entire 

 cell, not a very thin section of one; and second!}, thai ihere is no 

 counterstain. 



S. The Altmann method. — Samssonow (1910) and Meves (1910 a) 

 have both employed the Altniann method and liavt- shuwii that it 

 demonstrates mitochondria with g'reat clearness. 



I have found that the mitochondria in the ner\e cell can be 

 beautifnll}^ stained by Altmami's technique il890. \). 27 1: the results 

 of this method have already been desciibrd under the liradinu' of 

 neurosomes (fig. 5). Compare fig-. 5 with Held, 1897, idate Xlll. figures 1 

 and 2. and with Altmann, 1890, plate XI, fig. 2. 



4. The Benda method. — Even the Benda method cannot be said 

 to be specific for mitochondria; but it is the most widely used of all 

 our methods. One of the latest modifications of the original technique 

 (Benda, 1901) is that given by Meves and Duesberg (1907. p. 574). 

 T^reparations were made by it and by reference to fig. 4 it will be at 

 once evident that the fine deeply blue stained rods distributed between 

 the flakes of Nissl substance are identical in form and distribution 

 Avitli the bodies already described. Compare fig. 4 with Hoven. 1910. 

 plate XY, and with Duesberg, 1910a. plates XXVIII to XXX. 



Ô. Iroii hemato.rijJin metJiods. — Iron hematoxylin, in its various 

 modifications, is one of the oldest and one of the most used methods 

 for the demonstration of mitochondria. The staining and differentiation 

 are generally done according to the original insti'uctions of Martin 

 Heidenhain (1896, p. 186). it is in the fixation that the technique 

 chiefly varies. The preparation from which fig. 8 was dra^^"n was 

 fixed in Meves' modification of Fleniming"s fluid (^1908. p. 832) for 



Intcrnatiouale Monatsschrift f. Auat. ii. Plivs. XXIX. 31 



