1306 Journal of Applied Microscopy 



Baum. E. Ueber die punktformigen Kalkkor- ^^^ yellowish-white points sometimes 

 perchen (sogen verkalkte Glomerule) der seen on the surface of the kidney have 



Nierenrinde. Virchow's Archiv, 162 : 85-93, ^een regarded as calcified glomeruli. 

 1900. '^ ° 



In the great majority of cases they are 



not glomeruli, but cysts containing lime-salts. These cysts are of two kinds. 

 They are present in kidneys in which there is no evidence of chronic interstitial 

 changes. The larger, irregularly shaped cysts arise from the uriniferous tubules. 

 Their walls are lined in places with high epithelium. The cysts of the other 

 variety are round, about the size of a glomerulus and confined to the cortex. 

 They represent capsular spores of malpighian corpuscles, in which glomeruli have 

 not developed. The lining epithelium when present is of a low type. The 

 lime is deposited in the colloid material which fills the cysts. The lime occurs 

 as small granules and as concentric masses. Only rarely does a sclerosed glom- 

 erulus become calcified. j. h. p. 



whii^^., w c A r^ 1 J c- 1 A/r .u J The writer states that the various meth- 

 Wnitney, W. t. A Quick and Simple Method 



for Fixing the Blood Corpuscles for Differ- ods for the rapid fixation of blood 

 ential Staining. Jour. Boston Soc. Med. Sci. g^^^ars that have been devised are all 

 5: 341, 1901. 



uncertam. The method has given uni- 

 formly good results. It consists simply in the use of a modified Zenker's fluid. 

 This solution consists of a mixture of potassium bichromate two parts, sodium 

 sulphate one part, water 100 parts, saturated with corrosive sublimate, plus 5 

 per cent, of glacial acetic acid. In Whitney's modification 5 per cent, of strong 

 nitric acid is substituted for the 5 per cent, of acetic acid. 



The blood is drawn and spread in the usual way and dried thoroughly in the 

 air or, if preferred, by a gentle heat. The cover-glass is taken with the forceps, 

 the prepared surface covered with a few drops of the fluid and held while twenty 

 are counted slowly. It is washed off with running water and blotted. The 

 action depends upon the combination of corrosive sublimate with potassium 

 nitrate and chromic acid which are formed in the solution. 



Ehrlich's triacid stain, Unna's polychrome methylen blue and Chenzinski's 

 eosin work well after the fixation. j. h. p. 



Goldhorn, L. B. A Rapid Method of Staining 1- Fix fresh preparation by immersion 

 the Chromatin of the Malaria Parasite. in pure methyl alcohol for 15 seconds. 

 Med. Rec. 59: ii. ^ ,.r , • • 



z. Wash m runnmg water. 



3. Stain for 7 to 30 seconds in 0.1 per cent. aq. sol. of eosin. 



4. Wash in running water. 



5. Stain for 80 to 60 seconds in polychrome solution. 



6. Wash again and dry in air ; no filter paper or heat being used. 



If, on exposure to air, the dye becomes too alkaline, a few drops of a 4-5 per 

 cent, solution of acetic acid may be added. If this amount of acid proves too 

 much, add a few drops of a saturated aqueous solution of lithium carbonate. 

 The stain improves on keeping. c. w. j. 



