286 ])R. C. A. MAC MUNN ON MYOHSEMATIN AND THE HISTOHH5 MATINS. 
Amphibians. 
In Bufo vulgaris myohsematin occurs in the heart, and in the voluntary muscles 
mixed with oxyhemoglobin, it is well marked in those of the thigh. (Spectrum 8, 
Chart IV.) 
In Rana temporaria it occurs well marked in the ventricle and feebly in the auricle, 
in both places mixed with oxyhemoglobin. In faint traces in the thigh and calf 
muscles, which are very pale. Also in other muscles. (See spectrum 7, Chart IV.) 
In Salamandra maculosa it is present mixed with oxyhemoglobin in the ventricle ; 
in traces in the arm and leg muscles and elsewhere in the voluntary muscles. 
In the little green tree-frog (Tlyla arborea) the distribution of myohematin was 
more carefully studied, and here I may observe that its absence must not be concluded 
from the fact that the muscle does not show the bands at once. If present in the 
oxidised state they may be invisible, so that a reducing agent may be necessary to 
bring them out. In most cases I used sulphide of ammonium in water or Stokes’s 
fluid. It is present in Ilyla’s ventricle and in the auricle, in the flexors of thigh, 
and in its extensors ; in the tongue muscles in traces ; in the calf muscles ; in the 
muscles in anterior aspect of leg; in the muscles of arm and forearm, and in all these 
apparently it is the sole pigment. It is mixed with oxyhsemoglobin in the muscles of 
the back and sometimes in those of tongue. 
In the Axolotl (Siredon pisciformis) a feeble myohsematin spectrum was seen in the 
ventricle and auricles, faint traces in the abdominal muscles, in those of the tail, and 
in the muscles of the leg ; while in those of the tongue, and of the back only oxyhse¬ 
moglobin could be seen. In the “ red frog ” (species ?) myohsematin occurs in the 
ventricle and in various voluntary muscles, e.g., pectorals, muscles of thigh, of leg, 
and it was generally found mixed with oxyhsemoglobin. 
Reptiles. 
In a small mud turtle of the genus Trionyx the heart ventricle showed the myohse- 
matin bands so distinctly that I was able to measure them (approximately) :— 
1st band . . . X613 to 595, 
2nd band ... X 569 „ 563, 
3rd band ... X 556 ,, 550. (See spectrum 9, Chart IV.) 
The same bands are well marked in the pectoral muscles ; and in those of leg and 
arm feebly, 
In Lacerta viridis the same bands are well marked in the ventricle, and measured 
as follows 
1st band . . . X613 to X 593 (or X 595), 
2nd band ... X 569 ,, X 563, 
3rd band ... X 556 ,, X 550, 
4th band , , X 532 ,, X 513 (approximate). 
