296 BLOOD AND BLOOD EXAMINATION 



appear to be unsuitable for practice. [After using and teaching Ehrlich's 

 method as just described for eight years, I have recently discarded it in favor 

 of one of the " universal " stains which our author here condemns. Leishman's 

 "Eomanowsky" stain made up by Wright's method (see Journal of Med. 

 Research, 1902, vol. vii) is much quicker and easier to use, needs no fixing 

 fluid or heating apparatus, and gives pictures which in 99 cases out of 100 

 are superior to those obtained by Ehrlich's method. 



The technic is as follows: Adjust the cover-glass film in Cornet's forceps. 

 Flood it with the stain, using a medicine dropper and keeping the bottle 

 tightly corked when not in use. After one minute add water drop by drop 

 until a greenish iridescent scum appears on the surface. About 7 drops are 

 needed with a I inch cover-glass. Allow the stain, so diluted, to act two 

 minutes. Wash in water, and allow the preparation to stand one minute more 

 in water. Dry in blotting paper and mount in Canada balsam. 



This stain brings out all that Ehrlich's method does and, besides this, stains 

 the blood-plates, the granules of mast-cells, the chromatin of malarial parasites 

 and the basophilic granules in abnormal red cells — all points of value. 



The only weak point of the Eomanowsky stains is the deceptive resemblance 

 between certain megaloblasts, certain lymphocytes, and certain myelocytes. 

 In perhaps 1 case in 100 this troubles a beginner; in perhaps 1 in 1,000 

 it troubles an expert; but in no case- does this difficulty affect the essentials 

 • — the diagnosis, prognosis, or treatment of the case. — Ed. J 



In examining normal blood which has been stained according to these 

 methods we note the following important peculiarities : The red blood- 

 eorpuscles have been wholly stained with orange, that is, with eosin, and this 

 causes the unstained depression which is free from hemoglobin to stand out 

 prominently. 



Among the white blood-corpuscles the lymphocytes must be first mentioned 

 (see colored plate, Eow VII, a and I). Their nuclei show the above described 

 configuration, and on staining with a triacid solution they are moderately 

 well stained with methylene green, the protoplasm, however, being of a very 

 pale yellowish color. [The nuclei are often so faintly stained as to be nearly 

 invisible. The protoplasm frequently remains unstained or shows a faint gray 

 color. — Ed.] In methylene-blue eosin preparations the nucleus is deeply 

 stained with the blue stain, which is very frequently, however, found to be 

 more marked in the blue color of the rim of the protoplasm. This is an 

 expression of the fact that the protoplasm of the lymphocytes is more baso- 

 philic than its nucleus. In the not infrequent cases in which it is difficult to 

 determine the relation of a white blood-corpuscle to a definite cell grofup, this 

 condition is always a positive sign that the cell must be looked upon as a 

 lymphocyte; however, the absence of this reaction is not absolute proof that 

 the cell is not related to the lymphocytes, for, as may be noted from the 

 colored plate, the protoplasm occasionally shows a weaker stain with the 

 basic staining material than the nucleus. 



The cells which, in fresh blood, we have recognized as finely granular and 

 polynuclear, are sho^\Ti, in staining with the triacid stain (IX, 6) to have 

 pale green colored nuclei and very fine, almost dust-like granulations of a 



