24S CLINICAL DIAGNOSTICS. 



Transition forms occupy a position between the large 

 mononuclear leucocytes and the polynuclear leucocytes, their 

 nucleus being divided into two or three sections. They resem- 

 ble the mononuclears in their affinity for stains. 



3. Polynuclear Leucocytes. These are 10 to 12 micra 

 in diameter, are provided with a slender but broken and 

 irregular nucleus containing an abundance of chromatin and 

 a finely granular, opaque, neutrophile protoplasm. 



4. Eosinophile Leucocytes. These are 12 to 15 micra 

 in diameter, the body of the cell is filled with large roundish 

 granules which have an exceptional affinity for eosin and other 

 acid stains. They have one or two nuclei which are packed in 

 between the granules. The nuclei contain an abundance of 

 chromatin. 



5. Mast Cells. These vary in size up to that of the eosin- 

 ophyles, they have clumsy nuclei of various forms containing 

 little chromatin, and basophyle, coarsely granular protoplasm. 



According to Wiendick the varieties of leucocytes occur 

 in the following proportions in the blood of the horse : 



Actual No. 



per cubic 



Percentage, centimeter. 



1. Lymphocytes 35-45 2500-3500 



2. Mononuclear Leucocytes 1.5-3.5 150-300 



3. Neutrophyle Polynuclear Leucocytes 50-70 4000-5000 



4. Acidophvle Leucocytes 1.5-5.0 200-350 



5. Mast Cells (Basophyle leucocytes) . .0.2-0.7 20-60 



It is not unusual to observe even greater variations than 

 those shown in the table. 



A temporary increase in the actual number of leucocytes 

 (hyperleucocytosis) may occur after feeding and in animals 

 in advanced pregnancy. Such an increase is also observed in 

 the course of all infectious inflammatory processes, especially 

 during the formation of abscesses in the course of strangles. 



The actual number of leucocytes is reduced (hypoleucocy- 

 tosis) permanently in the course of pernicious anemia. In 



