'COLOURED' AND 'COLOURLESS* 165 



lidae they are bi-convex and oval. There is 

 no nucleus observable in the red corpuscles 

 of the human being. There are also a few 

 nucleated ' white ' corpuscles which contain 

 no haemoglobin. 



Ked and white corpuscles are now generally 

 known as ' coloured' and ' colourless.' 



The proportion of coloured corpuscles in 

 health is from between 400 and 500 to one 

 of the colourless, but in disease there are 

 only about ten coloured to one of the colourless. 



In the moist state the coloured corpuscles 

 of healthy blood form 45 per cent, by weight 

 of the whole mass of the blood. 



In the average healthy blood there are 

 5,000,000 corpuscles per cubic millimetre. The 

 colourless corpuscles are known as leucocytes. 

 The coloured corpuscles of the Camelidse have 

 no nucleus, but in birds, fishes, and reptiles the 

 corpuscles are oval, bi-convex, and nucleated. 



No corpuscle similar to the coloured cor- 

 puscle is found in the blood of invertebrate 

 animals, but bodies not unlike the colourless 

 corpuscles are seen. 



