FOWL TYPHOID 81 
Fow! fed culture March 26 
7 : saree of Meet of 
Date emperature red cor- white cor- 
(F°) puscles puscles Remarks 
perc, mm, per c, mm. 
Mar. 26 106.2 3,535,000 18,940 Well. 
28 110 2,430,000 70,000 Fowl eats very little. 
Apr. 2 110.6 1,684,210 80,000 Blood very pale; fowl weak; re- 
fuses food. 
8 106 1,745,000 245,000 Very weak; many red corpuscles 
attacked by leucocytes. 
Ae le ett ia nace ath ak wink cae e-card eran ean eect Found dead. 
In fresh preparations of the blood of affected fowls examined in 
Toisson’s fluid, red corpuscles which take the violet stain more or less 
intensely throughout are frequently observed. 
In the blood of poultry two distinct classes of white corpuscles 
are conspicuous. The first, which predominates in numbers, contains 
nuclei with from one to four lobes, and the cytoplasm is sprinkled 
with a variable number of round, elongated, or spider-shaped bodies. 
In the fresh condition they are highly refractory. They stain with 
eosin, and if the preparations are heated sufficiently they will retain 
certain of the aniline dyes. The other class consists of round or 
nearly round cells which takes the blue stain feebly. Usually it is 
difficult to detect the nucleus, although it is occasionally distinct. 
Between these two types there are many varieties. The leucocytes 
containing the spindle-shaped bodies appear to be the phagocytes, 
as they were the only ones which were observed to engulf the red 
corpuscles. Bacteria have not been demonstrated in these cells, 
although their presence has, in several cases, been suspected. From 
the appearances observed in the red blood corpuscles it seems highly 
probable that phagocytosis plays a comparatively large part in their 
destruction. Another hypothesis is also suggested, namely, that a 
toxin produced during the multiplication of the specific organism has 
this effect on the red corpuscles. In the fresh preparations we can 
observe the phagocytes attacking the red cells. In the stained ones 
mutilated red corpuscles and free nuclei are present. The hypothesis 
is suggested that the leucocytes partially digest certain of the red 
corpuscles in their attack upon them. Whether these changes are 
entirely attributable to the phagocytes is an open question. 
In the blood from healthy fowls it is comparatively rare to see one 
of the white corpuscles engulfing ared one. As the disease progresses, 
