132 



THE AMEKICAN MONTHLY 



[July, 



A chemical union between the cal- 

 cium phosphate and the dye occurs, 

 while the calcium carbonate is un- 

 affected. In three days the alizarin 

 disappears from the blood and other 

 organs. It may be found temporarily 

 in any part of the system, as in lymph, 

 gall, urine, faeces and saliva, but is 

 not permanent. 



54. Strelzoff'. Genetisc h -topo- 



graph ische Untersuchungen 



des Knochenwachsthums. 



Unters. a. d. Pathol. Inst. zvi. 



Zurich, 'herausg. von Eberth. 



1874. H. 2, p. 83. 

 Confirms Lieberkuhn's statements 

 that the madder unites with inorganic 

 portions of the bones. 



55. Benczur. Augegeben in v.Than- 



hofter. Das Mikroskop und 



seine Anwendung. 

 Von Thanhoffer describes an alco- 

 holic solution of alizarin as recom- 

 mended by Benczur for staining large 

 nei-ves. The sections should remain 

 twenty-four hours in the dye. The 

 cells and axis of the preparations will 

 be light brownish red. The contents 

 of the cells and the axis will be 

 sharply differentiated. 



56. Ranvier. Des applications de la 



purpurine al'histologie. Arch. 



d. Phys. 1874. p. 761. 

 Dissolve purpurin in a boiling so- 

 kition of alum 1-200 of water. Add ^ 

 part alcohol. The solution is an 

 orange-red. It dyes strongly the peri- 

 osteum, cornea, and nucleus of cartil- 

 age cells, bones, etc. Bioplasm re- 

 mains uncolored. This stain is much 

 to be recommended for the spinal 

 marrow hardened in ainmonium bi- 

 chromate, but specimens treated with 

 chromic acid and Miiller's fluid are 

 not good. In the spinal marrow^ the 

 nuclei of connective tissue and of 

 capillaries become red, but the nuclei 

 of nerve cells remain colorless. It 

 becomes thus a means of differentiat- 

 ing nerves from connective tissue. 



57. Grenacher. In hand-books of 



microscopy. 

 Dissolve a pinch of purpurin in a 



1-3% solution of alum in glycerin, 

 pure or slightly diluted. After stand- 

 ing 2-3 days, filter. Keeps longer 

 without a precipitate than Ranvier's 

 solution of purpurin, and stains in 

 from 10-30 minutes. 



VARIOUS DYES. 



58. Waldeyer. Ueber den Ursprung 



und Verlauf des Axencylin- 



ders bei Wirbelthieren und 



Wirbellosen. Zeitschr. f. rat. 



Med. 3. Reihe, Bd. xx. 1863. 



To stain the axis of nerve fibres 



without staining the sheath, a watery 



solution of the coloring matter of 



alkanet root is recommended. An 



extract made with turpentine has also 



done good service, producing similar 



effects. 



59. Dippel. Das Mikroskop, 2 Aufl. 



p. 721. 1882. 



Uses an alcoholic tincture of alka- 

 net in vegetable histology. It serves 

 particularly to distinguish resins and 

 fats, which color a deep red while 

 protoplasm only takes a rosy tinge. 

 Dippel thinks it would be useful for 

 animal tissues. 



Hai'tig. See No. 2. Alkanet, like 

 carmine, tends to concentrate in cell 

 nuclei. 1854. 



60. Lawson Tait. On the freezing 



process for section-cutting and 

 on various methods of staining 

 and mounting sections. Jour. 

 Anat. and Phys., vol. ix, p. 

 _ 250. 1875. _ 

 Tait rejects anilin dyes and car- 

 mine and strongly recommends 

 litmus. Boil powdered litmus in 

 water, filter, add a little alcohol. The 

 sections color uniformly deep blue. 

 By adding a very little nitric acid a 

 brownish red is obtained. Wash 

 quickly and thoroughly, and the nuclei 

 will be blue, the rest of the tissue a 

 rose pink. 



The leaves of the red cabbage ex- 

 tracted with water or alcohol may be 

 used with good results. The addition 

 of ammonia gives a green, of acid a 

 purple. But these are temporary 

 stains and not permanent. For quin- 

 olein and cyanin see the anilins. 



