290 DR. C. A. MAC MUNN ON MYOHXE MATIN AND THE HISTOELEMATINS. 
In the ventricle of the heart of the dog , the myohsematin bands read (Chart IV., 
spectrum 14) :— 
1st band ... X 613 to X 598, 
2nd band . . . X 569 ,, X 563, 
3rd hand . . . X 556 „ X 550. 
It is also present in the wall of auricle and auricular appendix, and in the general 
muscular system. 
In the same parts of the cat it is found abundantly; in the heart ventricle, after 
injection with salt solution, its bands read :— 
1st band . . . X 613 to X 596‘5, 
2nd band . . . X 569 „ X 563, 
3rd band ... X 556 ,, X 550. 
In the sheep, ox, and pig it also occurs in the same situations, and, lastly, it has 
been found in the heart and voluntary muscles of man. Its bands are seen with great 
distinctness in the musculi papillares of the human heart, and here its first band is 
narrower than usual, as shown in spectrum 16, Chart IV. 
Attempts to isolate Myohcematin, 
In myohsematin the coloured constituent is united to a proteid as in haemoglobin 
and enterohsematin, hence the difficulty which attends its isolation. I have already 
described some experiments on the myohsematin of insects ; on that of mammals a 
few experiments have also been made, but much yet remains to be done. 
It was necessary to endeavour to find out what relationship it bears to muscle 
plasma, as Kuhne * has shown that the haemoglobin of muscle belongs to the plasma. 
Accordingly this experiment was performed ; a rabbit was killed, the vessels at the 
base of the heart ligatured quickly, and both ventricles injected and well washed out 
with salt solution ; they were then quickly cut off at their junction with the auricles ; 
and after cutting them up, well washed with salt solution and put into a rag and 
frozen in a platinum vessel surrounded with a mixture of ice and salt ; when frozen 
they were removed and cut with an ice-cold knife, and pressure was then brought to 
bear on the mass in the rag ; a few drops of a reddish-yellow liquid exuded which 
was examined with the spectroscope. It showed the bands of oxyhemoglobin which 
appeared to me slightly changed from the normal as the second one seemed too dark, 
and on adding sulphide of ammonium this idea was found to be correct, as now the 
dominant myohsematin bands appeared in the usual position. 
In some filtrate thus obtained, just above a freezing temperature spectrum 17, 
Chart IV., appeared after adding some sulphide of ammonium. Hence a part of this 
* Loc. cit. 
