446 SUMMARY OF CURRENT RESEARCHES RELATING TO 



films of protoplasm and ordinary cellulose membrane are scarcely, if 

 at all, stained, starcli-grains not at all. By washing the objects in 

 water after staining, instead of in spirit, a grey-blue colour is ob- 

 tained : transference to concentrated glycerine makes the colour purer. 

 The colour comes out best, however, after washing in alcohol, treating 

 with oil of cloves and mounting in one of the resins (dammar or 

 Canada balsam). To avoid contraction, the clove oil may be diluted 

 with alcohol and allowed to concentrate uj)on the object by evaporation 

 of the alcohol. The watery solution is especially adapted for rapidly 

 killing and staining objects already under the Microscope. 



b. Nigrosin and picric acid may also be used in solution in alcohol ; 

 the solid acid and nigrosin are left for some time in absolute alcohol ; 

 by this solution the chromatoi^hores and pyrenoid are less deeply 

 stained, the coloured contents of the nucleus very deeply so. 



Anilin Colouring Matters as Staining Media for Human and 

 Animal Tissues.* — Dr. H. Griesbach discusses the value of anilin 

 colours as staining media for human and animal tissues, and gives the 

 results of his own experience. His paper is not capable of useful 

 abstract, being already in a condensed form, but the following brief 

 account is given to call attention to its existence and to enable reference 

 to be made to the original. 



Anilin-yellow he considers unsuitable. Sdure-geTb colours bone a 

 beautiful orange, tracheal cartilage and connective tissue lemon. In 

 sections of the intestinal sac of TJnio the epithelium is orange, muscle 

 gold, glandular tissue brownish, and the nuclei of the cells are very 

 clearly shown. Nerve-elements are not so well coloured, nor any 

 isolated cells except gland-cells. It does not appear to be suitable for 

 chromic acid preparations. Chrysoidin is useful for bone and all kinds 

 of connective tissue, which it colours a bright yellow. Its best effect is 

 with fresh preparations. Bismarck hroion has its best effect with 

 nuclei (either alcohol or chromic acid preparations) and unicellular 

 organisms, bacteria of all kinds, colourless blood-corpuscles, &c. 

 TropcEolin, Y, 0, 00, 000 No. 1, and 000 No. 2. The first is good 

 for human spinal cord hardened in chromic acid, and alcohol prepara- 

 tions of bone, the others serve for connective tissue, cartilage, nuclei, 

 and bone. The colours are lemon-yellow, straw-yellow, orange, 

 orange-red, and brown. Crocein he has found to be a very useful 

 medium. It colours bone, cartilage, muscle, and connective tissue 

 (whether fresh or alcohol or chromic acid preparations) a beautiful 

 purple-red. Eocellin colours bone and connective tissue, muscle, glands, 

 and epithelium cherry-red. Xylidinponceau, Ponceau EE, G, and 

 G G are not suitable for chromic acid preparations. The first gives 

 good colours with bone, connective tissue, and muscle. The second 

 gives red and scarlet-red colours. The third coloui-s bone dark orange ; 

 connective tissue, muscle, and epithelium saffron-yellow ; nerve sub- 

 stances bright yellow. The fourth has only been found useful for 

 bone, gelatinous connective tissue, and muscle, which it colours a bright 



* Arch. f. Mikr. Anat., xxii. (1883) pp. 132-42. 



