390 Proceedings of Royal Society of Edinburgh. [sess. 
neurotic fatal cases in women, and once in a case with grave 
cutaneous lesion (reported above). It is noteworthy that in 
muscles we have a haemoglobin derivative, myo-haematin, whose 
spectrum is very similar to urohaematoporphyrin. Whatever else it 
is, it is a reduction product, for oxidation causes its hands to dis- 
appear. We might note the anaemia in Addison’s and Hodgkin’s 
diseases ; and as to System II., that if it be destroyed over a pretty 
extensive area, as in a severe “burn,” we have haemoglobinuria — 
a paralysis of Hb0 2 -transforming power. 
Normally, then, we may regard muscles, skin, and connective- 
tissues as seats of a subsidiary formation of urobilin from a 
haematin derivative, which, if it be excessively reduced, gives rise 
to pathological urobilin ; if, owing to as yet most obscure devia- 
tions from healthy metabolism in these systems, it be only imper- 
fectly reduced, we then have, in not a few cases, urohaematopor- 
phyrin, and in very rare ones its less reduced dark red ally. The 
degree of completeness of the initial reduction determines which of 
these haematin derivatives is to appear, for the amount of subse- 
quent pulmonary oxidation and renal reduction is probably the 
same for all. 
[In certain diseases this would, of course, not be so, as in 
pneumonia, where pulmonary oxidation is deficient, more, then, 
of the chromogen and less of the pigment from the system in 
which the prominent lesion existed would be excreted.] 
