314 THE GROUSE IN HEALTH AND IN DISEASE 



Red cells without nuclei were occasionally found in the blood of Grouse. Such 

 non-nucleate cells, however, were very rare. 



At times there also appeared to be a number of free nuclei in the blood of 

 Grouse. In this connection we may note that Warthin (1907) found 16'5 per cent, 

 of degenerated cells in the blood of normal fowls. 



Erythroblasts occur in the blood of Grouse in small numbers. The cells, which 

 Erythro- are nucleated, are rounder than erythrocytes,and are devoid of haemoglobin. 

 The nucleus of an ery throblast is more spherical than that of an erythrocyte. 

 The general cytoplasm is homogeneous, staining blue with Giemsa's stain. 



The number of leucocytes found per cubic millimetre in the blood of apparently 

 healthy Grouse varied from 22,000 to 50,000, averaging about 32,000 per cmm. 



The average results of the differential counts of leucocytes of apparently healthy 

 Grouse may be tabulated thus : 



Lymphocytes . . . . . . 57 per cent. 



Large mononuclears . . . . . 19 



Polymorphonuclears (crystalloid eosinophiles) 20 ,, 



Eosinophiles (coarsely granular eosinophiles) . 3 ,, 



Mast cells (basophiles) . . . . . 1 ,, 



The difficult computations are those of the large mononuclears and lymphocytes. 

 There are many medium-sized mononuclears in Grouse, which different observers 

 would classify differently. 



The association of altered conditions of the blood with the presence of protozoal 



parasites has been noted already, and I have found certain alterations in the 



Patho- relative proportions of the blood cells of Grouse that harboured protozoa 



biood of Leucocytozoa, Spirocheetes and Coccidia while other differences are to 



be associated with helminthiasis. The results may now be summarised : 



(a) When Spirochceta lagopodis (vide chapter xiv. p. 323) was present in the 

 blood of Grouse, as it was to some extent in two specimens, the number of 

 When mononuclear leucocytes increased, and these leucocytes became slightly 

 associated enlarged and vacuolated (PI. XLV., Fig. 9). Levaditi (1901) noticed 

 SpirocJuEta the presence of vacuolated mononuclear leucocytes in the blood of 



lagopodis. 



fowls infected with Spirochceta gallinarum, together with mononuclear 

 and polynuclear leucocytosis. Balfour (1908) found vacuolated mononuclear 

 leucocytes in the blood of fowls suffering from spirochsetosis in the Soudan. The 

 infection of Grouse with S. lagopodis was probably not nearly as great as that of 

 fowls with S. gallinarum investigated by Levaditi and Balfour. 



