H/EMOPHILIA. 



Of all the many conditions in which the haemor- 

 rhagic diathesis is present, haemophilia is at once the 

 most interesting, the best understood, and the most 

 tragically dangerous. We will not stay to speak of 

 the curious problems of its inheritance, nor of the 

 well-known tendency to bruising, joint effusions, and 

 bleeding after the most trivial injuries. One or two 

 of its peculiarities, however, deserve a word of 

 mention, as they may throw a light on the production 

 of the haemorrhagic tendency. For instance, the 

 locality and the nature of the injury have some 

 significance. In a few cases, wounds below the neck 

 may not bleed to excess, whereas abrasions of the 

 most trifling description affecting the lips, cheeks, 

 or gums may baffle all attempts to stanch the flow. 

 Again, needle pricks, if small, do not bleed, probably 

 because the elastic skin seals over the opening ; it 

 is even safe to withdraw blood from a vein. Further, 

 it is not true that the haemorrhage never stops. It 

 may cease with or without treatment, sometimes 

 permanently, sometimes only to come on again later. 

 If a subcutaneous haematoma develops, the wall is 

 lined by well-formed clot, but the central portion 

 contains blood which shows no tendency to coagu- 

 lation in spite of the contact with clot. It is the 

 capillaries, rather- than the arteries, which continue 

 to ooze. 



It will be a matter of opinion whether under the 

 generic name of haemophilia we should include cases 

 that arise every now and then, in either sex, of a 

 congenital and persistent tendency to bruise and 



