DR. C. A. MAC MUM ON MY0H2EMATIN AND THE H1ST0H2E MATINS. 291 
pigment occurs in the plasma like haemoglobin. It is noticeable that its bands are 
merged into those of oxyluemoglobin, which accounts for their having been missed by 
others ; through the thin hazy band of reduced haemoglobin they are, however, readily 
seen. I missed seeing the band at D, probably owing to the small amount of plasma 
at my disposal. I failed to get the pigmented part of myoheematin by the use of any 
solvent into solution, thus the great pectoral muscle of a pigeon, which had been 
injected with salt solution, was cut up into small pieces, washed with salt solution and 
then strongly pressed ; after a second washing and pressing it was divided and portions 
put into—(1) an aqueous solution of caustic soda; (2) a rectified spirit solution of 
caustic soda ; (3) a rectified spirit solution with sulphuric acid ; (4) amyl alcohol. 
In the first solution I could find only hsemochromogen by the use of sulphide of 
ammonium : in the second a trace of changed myohaematin by using the same reagent; 
in the third only acid hsematin from the muscle haemoglobin ; and in the fourth a trace 
of lutein (= a lipochrome). 
By boiling the same muscle in rectified spirit and sulphuric acid a spectrum was 
obtained which was a mixture of acid haematoporphyrin with a decomposition product 
of myohaematin. The purple-red solution giving five bands, four of which read as 
follows :— 
1st band ... A. 640 to X 623, 
2nd band ... X 605 ,, X 594, (or 3) 
3rd band . . . X 582 „ X 576, (?) 
4th hand ... X 563 ,, X 545*5. 
By similar heating with caustic soda and rectified spirit only haemochromogen could 
be detected in the solution by adding ammonium sulphide. 
(5) Ether failed to take up any pigment, also (6) benzol, but (7) chloroform took 
up a trace of a pigment, the solution being faintly yellow and showing a very narrow 
band in green and two belonging to lutein. 
By the use of pepsine I succeeded in isolating a changed pigment. Some of the 
blood-free muscle from the ventricle of the heart of a sheep was cut up small, and 
after steeping in water for twelve hours, strongly pressed in a linen rag. This was now 
digested in a solution containing 0*6 per cent, oxalic acid (Kuhne) and a little 
pepsine for two hours at a temperature of 98° F. This solution, after filtering, showed 
two bands having some resemblance to hsemochromogen, but placed nearer violet. 
They are evidently similar bands to those seen as an exception in the thoracic muscle 
of the bee and the cockroach, &c., supra; they read :— 
1st band ... X 554*5 to X 548*5, 
2nd band ... X 524*5 ,, X 519* ( = narrow part). 
On adding some caustic soda the bands disappeared, but with ammonium sulphide 
* This second band does not, however, correspond to that of altered myoha3matin. 
2 p 2 
