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a solution of carmine in ammonia, from which the smell of 

 ammonia has disappeared, till sufficiently stained, i.e., three 

 to twenty minutes. Then it is well washed in distilled water, 

 agitated by blowing into it through a glass tube ; thence for 

 half a minute in a watchglassful of water with one drop of 

 acetic acid added thereto ; thence into absolute alcohol. 

 After ten minutes in this, all the water being extracted, it 

 is placed in oil of cloves, which completely clears it in a 

 minute or two; and then is mounted in solution of gum 

 Damar in turpentine — such as is sold by artists' colourmen. 

 This method is used by Meynert, the great student of brain- 

 structure at Vienna, and in the laboratories of Strieker, 

 Klein, Briicke, Wedl, and Rokitansky. Dr. Klein cuts, 

 stains, and mounts sections of the hen's blastoderm in twelve 

 minutes by this process. Glycerine is often used to mount 

 in after carmine staining, but is found not to keep so well. 

 Glycerine is used for mounting gold and silver-stained pre- 

 parations, but does not preserve them for more than a few 

 Aveeks or months — the staining becoming at length diffused 

 and uniform throughout. Any one Avho Avould suggest a 

 means of permanently preserving the beautiful silver pre- 

 parations of cornea and lymph- capillaries, &c., Avould perform 

 great service, and confer a boon on those who use these 

 admirable reagents. 



Nitrate of Silver Staining. — The weight of authority and 

 experience is uoav decidedly in favour of Von Reckling- 

 hausen's interpretation of results obtained from the use of 

 nitrate of silver. Perfectly fresh tissues are to be placed in 

 a half per cent, solution of silver, left for ten minutes, Avashed 

 and mounted in glycerine, and exposed to sunlight for half an 

 hour or more. Epithelium is to be brushed gently away before 

 excision if underlying tissues are to be stained. The frog's 

 cornea is admirably stained by scraping off the conjunctival 

 epithelium and rubbing with lunar caustic. In half an hour 

 the most marvellously beautiful demonstration of stellate la- 

 cuna; is obtained. Professor Strieker and Dr. Klein are clearly 

 of opinion that the cavities demonstrated in fibrous tissue, and 

 in the cornea, are not artificial products ; SchAveigger Seidel 

 still thinks they are ; Robinsky, having utterly failed in using 

 tlie method, tries to make out that Von Recklinghausen has 

 made the most childish misinterpretations. We have a gold 

 preparation Avhich shoAVS exactly the same stellate lacunas in 

 the cornea as do the silver preparations ; hence they are not 

 due to any special precipitation by silver. But Ave have not yet 

 heard of anybody Avho has patiently used the silver-method 

 and succeeded in making preparations, aa'Iio is not convinced 



