THE CORPUSCLES OF THE BLOOD. 45 



part of the cell body. These particles or granules, whether coarse or fine, 

 vary in nature; some of them, as shown by their greater refractive power, 

 their staining with osmic acid, and their solution by solvents of fat, are fatty 

 in nature; others may similarly be shown by their reactions to be proteid in 

 nature. 



The material in which these granules are imbedded, and which forms the 

 greater part of the cell body, has no special optical features ; so far as can 

 be ascertained, it appears under the microscope to be homogeneous ; no 

 definite structure can be detected in it. It must be borne in mind that the 

 whole corpuscle consists largely of water, the total solid matter amounting 

 to not much more than 10 per cent. The transparent material of the cell 

 body must, therefore, be in a condition which we may call semifluid, 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 shown 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 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 con- 

 nection 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 per cent, solution of sodium chloride or other neutral salt, it is, unlike 

 fibrin, speedily and wholly dissolved by a 10 per cent, 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, which we may speak of as being in a fluid con- 

 dition; and which on the death of the corpuscle 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 or identical with serum-albumin. 



In addition, there is present, in somewhat considerable quantity, a sub- 

 stance 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 

 nudein. 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 per cent.) of phos- 

 phorus, 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 the white 

 corpuscles, come certain fats. Among these the most conspicuous is the 

 complex fatty body lecithin. 



In the case of many corpuscles at all events we have evidence of the 



