106 



THE AMERICAN MONTHLY 



[June, 



paration of these seeds from Dr. 

 Gray, such as he is offering in the 

 Exchange column. The lattice-work 

 capsule is beautifully shown under a 

 2-inch objective, and makes a most 

 attractive object for exhibition. — Ed.] 



Staining Tissues in Microscopy.* — 

 III. 



BY PROF. HANS GIERKE. 

 \_Continued fro7n p. g4.'\ 

 HEMATOXYLIN, EXTRACT OF LOG- 

 WOOD. 



36. Waldeyer. Untersuchungen iiber 



den Ursprung und den Verlauf 



des Achsencylinders bei Wirbel- 



thieren und Wirbellosen. Henle 



und Pfeufer's Zeitschr. f. ratio- 



nelleMed. 3 Reihe. Bd. xx,p. 



200. 



Waldeyer tried to stain the central 



axis of nerves with carmine and ani- 



lin and also with logwood, alkanet 



and Brazil wood. He obtained good 



results only with alkanet. The watery 



extract of both dye-woods stained too 



deeply, and did not differentiate the 



axis. 



37. Bohmer. Aerztl. Intelligenzb. 



f. Baiern, 1865. No. 38. 



1. Hematoxylin in crystals, 0.35 

 gm. ; absolute alcohol, 10. o gm. 

 Dark brown fluid ; does not spoil. 



2. Alum, 10 gm. ; distilled water, 

 30.0 gm. 



Add a few drops of No. i to No. 

 2, according to the strength desired. 

 The result is a deep bluish violet 

 fluid. The first solution improves 

 with age. The mixture should be 

 made three or four days before using, 

 and exposed to the light, or it will 

 stain too darkly. The fluid keeps 

 well, but requires filtering in sum- 

 mer. It dyes specimens hardened in 

 chromic acid as well as in alcohol, 

 but requires care to prevent over- 

 staining. If this happens, acids — 

 especially acetic acid — may be used 

 to wash out the excess of color, but 



* From the Zeitschri/t filr wissenschaftiiche Mi- 

 kroskopie. Translated for this Journal by Prof. 

 Wm. H. Seaman, M. D. 



preparations thus treated are less per- 

 manent, and in the course of years 

 some bleaching takes place, espe- 

 cially when chromic acid has been 

 used. 



38. Frey. Die Hematoxylin farbung. 



Archiv. mikrosk. Anat., Bd. iv, 



P- 345- 

 Frey recommends Bohmer's fluid. 



For preparations hardened in chromic 



acid, potassium bichroinate, or copper 



sulphate the alum may be omitted ; 



the alcoholic solution of hematoxylin 



is merely diluted with water. Frey 



thinks the action on chrome prepara- 



tiohs is similar to that of Leykauf's 



ink. (See Wagner's Chem. Tech- 



nol., 3 Aufl., p. 532.) 



39. Merkel. Der quergestreifte Mus- 



kel. Arch, mikrosk. Anat., Bd. 



ix, p. 293. 

 The double refracting portions of 

 muscular tissue stain readily with ex- 

 tract of logwood ; other parts remain 

 uncolored. 



40. Arnold. Logwood as a staining 



material for animal tissues. 



Quart. Journ. Micr., 1873. p. 



86. 

 Rubs up logwood with three times 

 as much alum, digests in water, and 

 adds one-fourth as much 25% alco- 

 hol. (Can only take the place of 

 Bohmer's fluid when no crystals are 

 to be obtained.) 



41. Lawson Tait. Journ. of Anat. 



and Physiol., vol. ix, p. 250. 

 Recommends that preparations 

 stained with hematoxylin should be 

 treated with 4% nitric acid. The 

 nuclei will then show brown on a 

 cherry red ground. (Preparations 

 thus treated soon bleach out.) 



42. Kleinenberg. In ' Grundzuge 



der Entwickelungsgeschichte 

 der Thiere,' by Foster and 

 Balfour. Leipzig, 1876. 

 Three solutions are to be made : — 



1 . Saturated solution crystallized cal- 

 cium chloride in 70% alcohol, to which 

 add as much alum as it will dissolve. 



2. Saturated solution of alum in 70% 

 alcohol. Mix 2 with i in the pro- 



