Table 12. — Dimension of erythrocytes 



Breed 



Single Comb While Leg- 

 horns. 



Average for group . . . 

 Single Comb White Leg- 

 horns. 



Average for group . 

 New Hampshires . . . . 



Average for group . . 

 Columbian Plymouth 

 Rocks. 



Average for group . , 



Source ' 



RPL6. 



RPL 15 . 



-commercial 



Commercial 



Bird 2 



Cytosome 



Length 



Range 



9.6-11.8 



10. 0-11. 6 



9. 7-11. 8 



9. 2-11. 4 

 9.4-11.6 

 9. 3-11. 6 



10. 9-14. 

 10. 6-13. 4 

 10. 9-13. 2 



11.0-13.4 

 11.2-12.9 

 10. 9-14. 2 



Aver- 

 age M 



10.8 

 10.8 

 10.7 

 10.8 

 10.6 

 10.3 

 10.4 

 10.4 

 12.4 

 12.1 

 12.0 

 12. 2 

 12! 4 

 12.0 

 12.6 

 12.3 



Width 



Range 



6. 2-8. 

 .5. 9-7. 7 

 6. 0-7. 7 



Aver- 

 age M 



7.0 

 6.6 

 6.6 

 6.7 

 6.7 

 6.5 

 6.7 

 6.6 

 6.8 

 7.2 

 6.5 

 6.8 

 6.9 

 6.7 

 7.0 

 6.9 



Nucle 



Length 



Range 



3. 4-4. 9 

 3. 6-4. 6 

 3.4^.6 



Aver- 

 age M 



4.3 

 4.1 

 4.1 

 4.2 

 3.8 

 4.1 

 4.3 

 4. 1 

 4.9 

 5.1 

 5.2 

 5.1 

 5.9 

 5.0 

 5.5 

 5.5 



Width 



Rang 



M 



2. 7-4. 1 



2. 7-3. 5 



3. 0-3. 5 



1. 8-3. 6 



2. 8-3. 4 

 2. 6-3. 7 



3. 0-3. 7 

 2. 7-4. 1 

 2. 8-3. 5 



2. 0-3. 7 

 2. 5-3. 6 

 2. 8-4. 4 



Aver- 

 age M 



3.1 

 3.1 

 3.2 

 3.1 

 3.0 

 3.0 

 3.1 

 3.0 

 3.4 

 3.3 

 3.2 

 3.3 

 2.8 

 3.3 

 3.3 

 3.1 



' RPL = stock from the U. S. Regional Poultry Research Laboratory. 



2 Measurements based on 25 cells per bird. 



1,028.000; age 10-15 days, hemoglobin 6.8 per- 

 cent, number of erythrocytes 1,645,000, area of 

 an erythrocyte 74.5ju"; age 16-20 days, hemo- 

 globin 7.7 percent, number of erythrocytes, 

 2,177,000 area of an erythrocyte 72.7m"; and 

 age 21-30 days, hemoglobin 11.4 percent, num- 

 ber of erythrocytes 2,425,000, and area of an 

 erythrocj^e 55.8^'. Essentially similar changes 

 in increase of hemoglobin and cell number, and 

 decrease in cell size with age, occurred in the gull. 

 Lams ridibundus L., which have praecocial 

 young. 



Bartsch et al. (1937) gave average length and 

 width of erythrocytes and length and width of 

 their nuclei for 50 species of birds from eastern 

 North America. They say (p. 516) : 



"The largest cell was found in the Osprey, 

 which yielded the length 16.5 microns, while the 

 smallest length was observed in the Carolina 

 Chickadee, which gave a length of 6.0 microns. 

 The greatest diameter of the cell was found in 

 the Osprey and the Red-headed Woodpecker, 

 both of which gave a reading of 10.0 microns, 

 while the Eastern Ti-ee Sparrow yielded the least 

 diameter, namely 4.0 microns. 



"In the measurements of the nucleus the larg- 

 est diameter fell to the Red-headed Woodpecker, 

 which yielded 7.87 microns, while the shortest 

 length of the nucleus fell to the White-breasted 



Nuthatch and the Yellow-throated Warbler, both 

 registering 3.10 microns. The greatest diameter 

 of the nucleus fell to the White-breasted Nut- 

 hatch and the Eastern Hermit Thrush, both of 

 which yielded 1.10 microns." 



These authors listed five earlier papers, not 

 quoted here, in which erythrocyte size had been 

 determined in wild birds. 



Table 13 gives measurements of length and 

 width of thrombocytes for the same four groups 

 of chickens. Nuclear measurements were not 

 taken. The cells in the New Hampshire and in 

 the ColumJjian Plymouth Rock were about 1 

 micron longer than in the Laboratory stock of 

 Single Comb White Leghorns, and the width was 

 greater also. 



The irregular shapes of the lymphocytes and 

 monocytes make it impossible to take simple 

 length and width measurements. This irregu- 

 larity of form is shown in figures 150 and 151. 

 On page 65 it was explained that the areas were 

 determined by tracing the outlines of cells and 

 nuclei with a camera lucid a and then using a 

 planimeter. The diameters given in table 14 are 

 calculated values derived from the areas. The 

 areas of lymphocytes for the three groups, RPL 

 6, RPL 15, and the Columbian Plymouth Rocks, 

 were close — 54.7, 52.6, and 54.2yu", respectively. 

 But the average area for the three New Hamp- 



212 



