^ 



Figure 413. — A box and cover suitat)le for carrying 15 tubes for the hemoglobin test, tlie same number 

 of Van Allen hematocrit tubes, and red-cell pipettes. The tray holding the lf,st of these can be 

 lifted out and stored in the refrigerator until they are ready for counting. Front compartments 

 carry hemoglobin pipettes, knife, cotton bats, and rubber tubes for drawing up blood and fluids. 



it in the refrigerator, where it remains until other 

 procedures involving the hemoglobin and the Van- 

 Allen hematocrit tubes have been completed. 

 The box with clean slides and the infrared lamp 

 are separate items; they are not included in the 

 box used for collecting blood samples. 



STAINING 



Selection, preparation, and use of tFright^s 

 stain 



Solutions containing dried Wright's powder 

 have been made at the Laboratory and used; 

 commercially prepared solutions have also been 

 used. The difficulty in finding a Wright's stain 

 suitable for avian blood has been discussed by 



Denington and Lucas (195.5). When dried 

 powder was used, 3.3 grams were added to a 

 500-cc. bottle of pure methyl alcohol, freshly 

 opened. This quantity of stain is approximately 

 double the cpiantity used in making Wright's 

 stain for human-blood studies. The stain is 

 ripened for several months either at room tem- 

 perature or in the incubator at 38 to 40 degrees 



centigrade 



A great many samples of dye, both from pow- 

 ders made up into solution at the Laboratory and 

 from liottles of the dye that had been put into 

 solution ])y a supply house, were tested. Some 

 gave too red a color to the cytosomes of erythro- 

 cytes and gave pale, incompletely stained nuclei, 

 and others stained the nuclei very intensely but 

 gave a pale bluish color to the cytosomes of 

 erythrocytes. The color balance of other cell 



228 



