Plethora. Polyamia. 369 



(domestic animals 1:800, i : iioo, Nocard). The variation in 

 different parts of the vascular system and at different times of the 

 day is striking and suggestive. 



In the blood of the splenic vein i : 60 ; in the hepatic vein 

 I : 170 ; in the portal vein i : 740 ; in the morning, fasting i : 716 ; 

 half an hour after breakfast, i : 347 ; in boys i : 226 ; in girls 

 I : 389 ; in men 1:346; in old men 1:381; in menstruating 

 woman i : 247 ; in pregnant woman i : 281, (Strieker). 



PI^ETHORA. POIrY^MIA. 



Definition. Transitory only. Causes, kidney disease, drinking freely, 

 rich feeding, profuse secretion, polycythemia, hyperalbuminosa, excess of 

 fibrine, sugar or fat. Ratio of blood to body. Variations of globules. 

 Symptoms, general, local. Appearance of blood. Prevention. Treat- 

 ment. 



Definition. An excess of blood, of the blood globules, or of 

 the albuminoids. 



Formerly accorded an important place in pathology, plethora 

 has been entirely eliminated from some recent works. The actual 

 amount of blood varies greatly_ at different times, rising after a 

 free consumption of food or drink, and falling during a period of 

 abstinence. A healthy activity of the secretory and excretory 

 organs secures a fair uniform average in the plenitude of the cir- 

 culatory system. Moreover, large variations are not in them- 

 selves rapidly injurious. Worm-Miiller and Cohnheim intro- 

 duced into dogs ten to twelve per cent, of the body weight (fifty 

 to eighty per cent, of their blood) of canine blood without induc- 

 ing fatal results. More than this was fatal. In non-fatal cases 

 a reduction to the normal standard is speedily secured. 



But we cannot count on absolute immunity in all circumstances. 

 Disease of the kidneys, or drinking water to excess, determines a 

 surplus of water and urinary salts (serous plethora, polysemia 

 aquosa). In cases of rapid gain in condition from rich feeding, 

 and above all after profuse watery secretion (diarrhoea, diuresis, 

 24 



