1 900 DISEASES OF THE CIRCULATORY SYSTEM 



Leucoeytosis, or increase in their numbers, may occur in physio- 

 logical conditions such as infancy, pregnancy, digestion, and 

 exercise, and there is a terminal or agonal leucoeytosis before death. 

 In pathological conditions a leucoeytosis due to polymorphonuclear 

 leucocytes may occur in septic or inflammatory coui^itions, many 

 fevers and toxaemias, after haemorrhage, and with malignant disease. 



Lymphocytosis may be relative when there is a relatively high 

 percentage of lymphocytes and low of polymorphs, with no increase 

 in the total number of white cells, or absolute when the total number 

 of white cells as well as of lymphocytes is increased. The former 

 occurs in protozoal infections such as malaria, amoebic dysentery, 

 etc., and the latter in leukaemia, etc. 



Eosinophilia, or increase in the eosinophile leucocytes, occurs 

 in helminth infections, in skin diseases, in asthma, in toxic states, 

 and in myelocythaemia. 



Basophilia occurs in myelocythaemia and staphylococcal infections, 

 but in the latter only slightly. 



Blood Platelets. 



These are probably derived from the erythrocytes, and may 

 possibly not be present in normal circulating blood, but formed in 

 preparing the films. Their clinical value is not absolutely certain. 

 They are said to number about 300,000 per cubic millimetre in 

 health. They are colourless, retractile, discoidal bodies, some 

 1-3 microns in diameter, having a great tendency to adhere together 

 and having an affinity for basic dyes. 



Hsemoconia. 



These are colourless retractile bodies, 0-5-4 microns in diameter, 

 which do not colour with ordinary stains and are of unknown origin 

 and function, though they may be fat particles, as shown by 

 Neumann. 



BLOOD PUZZLES. 



Blood puzzles consist of bodies which from the first have been 

 recognized as such or in other instances have been thought to be 

 parasites. 



It is difficult to give a systematic account of these bodies, but, 

 following Balfour, we may classify them as follows: — 



A. Heterogenetic: — Not in the blood. 



B. Autogenetic: — Actually in the blood. 



I. Found in fresh blood: — 

 (a) Erythrocytic. 

 {b) Leucocytic. 



II. Found in stained blood: — 

 (a) Erythrocytic. 

 {b) Leucocytic or lymphocytic. 



