SOME OTHER HISTOLOGICAL METHODS. 445' 



804. Bone, Decalcified (FI.EMMING, Zeit. f. wiss. Nik., 1886,, 

 p. 47). Sections of decalcified bone are soaked in water, and 

 brought in a drop of water on to a glass plate, where they 

 are spread out flat. The excess of water is removed with 

 blotting-paper, and the sections are covered with another 

 glass plate, to prevent them from rolling. The whole is 

 brought into a plate and covered with alcohol. After the 

 lapse of half an hour the sections have become fixed in the 

 flat position, and may be brought into absolute alcohol 

 without risk of their rolling. To mount them, wash them 

 with fresh alcohol (which may be followed by ether) ; lay 

 them again flat on glass, and cover them with a double layer 

 of blotting-paper and a somewhat heavy glass plate, and 

 let them dry for a day in the air or in a stove. When they 

 are dry, put a drop of melted balsam on a slide, and let it 

 spread out flat and cool. Prepare a thin glass cover in the 

 same way, put the section on the prepared slide, cover it 

 with the prepared cover, put on a clip, and warm. 



By this process sections can be very expeditiously pre- 

 pared, which show the lacunar system injected with air in 

 quite as instructive a manner as non-decalcified sections. 



805. Stains for Cartilage (and Decalcified Bone). For an 

 excellent discussion (especially as regards staining) of the 

 methods for these objects, see the exhaustive paper of 

 SCHAFFER in Zeit. f. wiss. Mik., v, 1, 1888. 



KOLLIKER (Zeit. f. icis-s. ZooL, xliv, 1886, p. 662) recom- 

 mends the following for the demonstration of the fibres of 

 Sharpey in decalcified bone. Sections are treated with con- 

 centrated acetic acid until they become transparent, and are 

 then put for one quarter to one minute into a concentrated 

 solution of indigo-carmine, then washed in water and mounted 

 in glycerin or balsam. In successful preparations the fibres 

 of Sharpey appear stained of a pale or dark red, the remain- 

 ing bone substance blue. 



ZACHAEIADES (Zeit.f. wiss. Mik., x, 4, 1893, p. 447) has the following : 

 Bone is decalcified by means of picric acid, washed, and put into alcohol and 

 sectioned. The sections are placed on a slide and treated for a few seconds 

 with 1 per cent, solution of osmic acid. They are then stained, either for 

 twenty-four hours in a weak aqueous solution of quinolein blue, or for a few 

 minutes in a saturated aqueous solution of safranin. They are then treated 



