Tlie reliiiidiis of iiiitiHiimidri.i ;iiiil (itlnr cytoiìlasmi«- constituents etc. 4H5 



must be trcntcil with Iji^m,]-, umIiu.- (,|n. tui- iiliniit III sec, ;,ii<l waslieil 

 ill ilisliilcd v\;ilrr In innove the sul)lim;ttc. 



4. Dilute the iilcoholir slork soliilioii of Mm- i\\r witli :n\ i->\i[:i\ volume of 

 a((. (list., am! stain for fio m ."< min. to J In-. 



5. Blot, (jiiickly with several layers of liltn |ia|Hr. 



6. Plunge into pure acetone and pass immediately tu toluol without wait- 

 ing to drain. 



7. Examine under the oil immersion and if necessary differentiate in oil of 

 oloves. If this is not sufficient, the slide, after rinsing in al)S. ale. may 

 be instantaneously flooded with '.lô"/» ale, anil then passed baid< tlii-oui.'h 

 abs. ale. to toluol. 



8. Wash in two changes of toluol and inoiinf in lialsam. 



In successful preparations tlie Nissl .^iihstaiiee takes n|i the >a- 

 franin and appears brig-lit red. Avliilc tlic acid vizier stains a series 

 of smaller gTanulations a greenisli bine culdiir (lii^-. 11). Tliesr tine 

 granules are seen, thickly aggregated in tlie ivizidii ^l ilir a.Mdit^ 

 hillock. The}" are in part only mitochondria, some of tln^ni beino the 

 neurosomes which Held observed in his erytlimsin-inethylene Idue 

 preparations. 



Neutral pyronin-m ethyl blue and neutral safranin-nu'îhyl bine 

 are made in the same manner by adding a saturated a(|neens snjntinn 

 of methyl blue to a saturated aqueous solutimi of pynniin er satranin. 

 They are both used in the same Avay as neutral safranin. Excellent 

 results were obtained with pyronin-methyl blue, ^v]li^ll is a litrle nnne 

 constant in its action than neutral safranin. 



Safranin-methyl blue does not give so brilliant pirtures. All 

 three dyes show the same structures in the same relation. Tliey may 

 be employed after a variety of fixations, such as. ('arui^y's (î : ;ì : 1 ilnid. 

 formalin-Zenker, 95*^/(, ale. etc., in addition to chronie-subliniate. 



9. Kimishurifs modification of the (LsSo) Weigert houdto.r/fihi 

 method. — Kingsbury (1911, p. 317Ì has made use of the A\'eigert 

 method, with a preliminary fixation in Zenker's fiuid. tor the ilemon- 

 stration of mitochondria in the lipoid-coutainiug eells of tlie ovary ami 

 suprarenal. This method was applied to spinal ganglion cells of the 

 pigeon. The only change in the procedure, as outlined 1»y Kingsbuiy. 

 was that the fixation in Zenker's fiuid. which contained only 0.5*^ ^, 

 acetic acid, was reduced from two days to two hours. After mor- 

 danting in Müllers fiuid the tissues were dehydrated, cleared in ber- 



