DR. C. A. MAC MUNN ON MYOHAEMATIN AND THE HISTOHHSMATINS. 289 
Biceps of forelimb, M and H ; triceps, M and H ; latissimus dorsi, M and traces of 
H ; trapezius, M and H ; muscles connecting skull to spine, M and H ; tail muscles, 
II; flexors of forearm, M and H ; extensors, M and H ; sartorius (?), M and H ; other 
thigh muscles, M and H ; tibialis anticus, M and H ; gastrocnemius, M ; abdominal 
muscles, M and H ; so that in all the voluntary muscles examined, we find myohae- 
matin, except in those of tail. 
In the gizzard of the same bird there are also decided traces of myohsematin, but 
oxyhsemoglobin is the pigment to which it mainly owes its red colour. 
I have also examined other birds, and in all of them the results were the same as 
those described. 
Mammals. 
In the hedgehog's heart,—auricle, ventricle, and auricular appendix, all give the 
spectrum of myohsematin. It also is found in most, if not all, the voluntary muscles 
mixed with oxyhemoglobin. The same is the case in the guinea-pig, and in the 
rabbit (spectrum 12, Chart IV.) ; from an inspection of this spectrum it is seen 
that the bands are the same as those of myohaematin found elsewhere, and give the 
same readings. The following will show the distribution of myohaematin in the 
voluntary muscles of a rabbit; (putting H = Haemoglobin and M = Myohaematin) :— 
Diaphragm principally H; pectoralis major, H and traces of M; sub-scapularis, H; inter- 
costals, H ; sterno-mastoid, M and H ; rectus abdominis, H; obliquus externus, H ; 
latissimus dorsi, H ; supra-spinatus, H and M ; infra-spinatus, H and M; masseter, 
M and H ; biceps of arm, M and H ; triceps of arm, M and H ; extensors of forearm, 
M and H ; flexors of forearm, M and traces of H ; psoas magnus, H ; gluteus maximus, 
H and traces of M ; rectus femoris, M and H ; an adductor of thigh, II ; vastus 
externus, M and H ; gracilis, H ; vastus interims, M and H ; tibialis anticus, M and H ; 
gastrocnemius (external head), M, and (internal), H ; flexor communis digitorum, 
traces of M and H ; other flexors of leg, ditto. 
In the heart of the hare the band of myohaematin at D of the normal spectrum is 
replaced by two (spectrum 18, Chart IV.), and these bands with the others gave 
approximately the following readings ;— 
1st band ... X 613 to X 600, and shading X 393 to X 582. (?) 
2nd band . . , X 569 ,, X 563, 
3rd band ... X 556 ,, X 550, 
Here the inter-auricular septum gives both myohaematin and oxyhaemoglobin, so 
does the auricular wall and appendix. In the ventricle, auricle, and auricular 
appendix of the rat, and in its voluntary muscles, the former pigment is found abun¬ 
dantly; in the ventricle the bands read (Chart IV., spectrum 15) :— 
1st band ... X 613 to X 596'5, 
2nd band . . . X 569 „ X 563, 
3rd band ... X 556 ,, X 550. 
In the mouse the bands are the same. 
2 p 
MDCCCLXXXVI. 
