706 PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



in preventing coagulation is removed and a clot of myosin forms. This 

 is first a jellying through the whole liquid ; the clot subsequently con- 

 tracts, squeezing out a colorless fluid or salted muscle-serum ; this does 

 not occur if the temperature is kept about C., and it occurs much 

 more quickly at the temperature of the body than at that of the air. 

 The formation of the clot at 36 C. takes, as a rule, five or ten minutes; 

 at the temperature of the air, several hours. The formation of the clot 

 is accompanied by the development of an acid reaction due to sarco- 

 lactic acid ; in this the formation of myosin contrasts with that of fibrin. 

 The resemblances between the coagulation in muscle and in blood is, 

 however, so striking as to suggest that the cause is similar; namely, a 

 ferment in both cases. The theory most generally accepted regarding 

 the formation of fibrin is that it is the result of a ferment action on a 

 previously soluble proteid of the globulin class occurring in blood- 

 plasma, called fibrinogen ; and the theory Dr. Halliburton now puts 

 forward is that myosin is also the result of a ferment action on a 

 previously soluble globulin occurring in a muscle-plasma, for which he 

 proposes the name myosinogen. This ferment can be prepared from 

 muscle in the same way as Schmidt's fibrin ferment is prepared from 

 blood ; muscle is kept for some months under alcohol, dried, and 

 * extracted with water. This aqueous extract contains the ferment, and 

 on adding it to the salted muscle-plasma coagulation occurs much more 

 quickly than if water alone be added. Myosin ferment is not identical 

 with fibrin ferment, as it does not hasten the coagulation of salted blood- 

 plasma, nor does the fibrin ferment hasten the coagulation of muscle- 

 plasma. The aqueous solution of the n^osin ferment gives the reaction 

 of a proteid of the albumose class, and especially of that variety of 

 albumose to which Kiihne and Chittenden have given the name deutero- 

 albumose. This is the same albumose as will be shown presently to 

 exist normally in the muscle-plasma. 



The proteids of muscle-plasma can be separated by fractional heat 

 coagulation, by fractional saturation with neutral salts, and by the 

 occurrence of spontaneous coagulation and the separation of the plasma 

 into clot and serum. The proteids were found to be five in number; the 

 names Dr. Halliburton proposes for them and their chief properties are 

 as follow : 



1. Paramyosinogen. This forms a flocculent heat coagulum at 47 C. 

 It is precipitated from its solutions in an uncoagulated condition (that 

 is, it can be redissolved in weak saline solutions) by magnesium sulphate 

 or sodium chloride ; by the former, when the percentage of salt present 

 reaches 37 to 50 ; by the latter, when the percentage reaches 15 to 26. 

 The precipitate so obtained occurs in white, curd-like flocculi. It is 

 precipitated also by dialyzing out the salts from its solutions. 



