40 COMPOSITION OF WHITE CORPUSCLES. [BOOK i. 



must therefore be in a condition which we may call semi-fluid, or 

 semi-solid, without being called upon to define what we exactly 

 mean by these terms. This approach to fluidity appears to be 

 connected with the great mobility of the cell body as shewn in its 

 amoeboid movements. 



29. When we submit to chemical examination a sufficient 

 mass of white corpuscles separated out from the blood by special 

 means and obtained tolerably free from red corpuscles and plasma 

 (or apply to the white blood corpuscles the chemical results 

 obtained from the more easily procured lymph corpuscles which 

 as we shall see are very similar to and indeed in many ways 

 closely related to the white corpuscles of the blood), we find that 

 this small solid matter of the corpuscle consists largely of certain 

 proteids. 



One of these proteids is a body either identical with or closely 

 allied to the proteid called myosin, which we shall have to study 

 more fully in connection with muscular tissue. At present we may 

 simply say that myosin is a body intermediate between fibrin and 

 globulin, being less soluble than the latter and more soluble than 

 the former; thus while it is hardly at all soluble in a 1 p.c. solution 

 of sodium chloride or other neutral salt it is, unlike fibrin, speedily 

 and wholly dissolved by a 10 p.c. solution. Myosin is further 

 interesting because, as we shall see, just as fibrin is formed in the 

 clotting of blood from fibrinogen, so myosin is formed out of a 

 preceding myosinogen, during a kind of clotting, which takes place 

 in muscular fibre and which is spoken of as rigor mortis. And we 

 have reasons for thinking that in the living white blood corpuscle 

 there does exist a body identical with or allied to myosinogen, a 

 body which we may speak of as being in a fluid condition ; and 

 that on the death of the corpuscle this body is converted, by a kind 

 of clotting, into myosin, or into an allied body, which being solid, 

 gives the body of the corpuscle a stiffness and rigidity which it 

 did not possess during life. 



Besides this myosin or myosin-like proteid, the white corpuscles 

 also contain either paraglobulin itself or some other member of the 

 globulin group, as well as a body or bodies like to or identical with 

 serum-albumin. 



In addition there is present, in somewhat considerable quantity, 

 a substance of a peculiar nature, which since it is confined to the 

 nuclei of the corpuscles and further seems to be present in all 

 nuclei, has been called nuclein. This nuclein, which though a 

 complex nitrogenous body is very different in composition and 

 nature from proteids, is remarkable on the one hand for being 

 a very stable inert body, and on the other for containing a large 

 quantity (according to some observers nearly 10 p.c.) of phosphorus, 

 which appears to enter more closely into the structure of the 

 molecule than it does in the case of proteids. 



Next in importance to the proteids, as constant constituents of 



