364 



Profs. J. G. Adami and L. Aschoff. [June 6, 



spherocrystals seen by us are merely dissociation products combined with 

 the introduced base. 



One striking feature is possessed by all these crystalline fluids, that, namely, 

 of dissolving other substances and still undergoing crystallisation. Ordinary 

 crystalline substances can only dissolve substances that are strictly 

 isomorphous ; these can dissolve other fluid-crystalline substances in all 

 proportions and have a generous capacity for dissolving substances of other 

 orders also. This fact bears intimately upon the varying microchemical 

 reactions exhibited by myelin bodies even in the same specimen. This 

 dissolving power alone is of high significance if, as indicated, diffused myelin, 

 or myelins of lecithin-like nature, are essential constituents of the cells of 

 most tissues. The lecithin, present in abundance in the red corpuscles, well 

 fits them to be the common carriers of the organism. 



Associated with this is the fact that admixture lowers the melting and the 

 clearing points ; so that of two globules of myelin, one containing admixed 

 more fatty acid or neutral fat than the other, the one may present itself as a 

 strictly fluid globule — isotropous — the other as a crystalline fluid globule — 

 auisotropous. Similarly, the surrounding menstruum has a profound effect. 

 IV e found with cholesteryl oleate that, using water as a menstruum, we could 

 not by any means gain spherocrystals ; at Professor Schenck's advice we 

 employed, with success, a minimal amount of dilute alcohol ; using a larger 

 quantity, the result was that the compound remained for days completely 

 isotropous, only as the alcohol slowly dissolved out of the oily mixture did 

 spherocrystals appear at the periphery. It may here be noted that pure 

 cholesteryl oleate is in the intermediate state at room temperature (15° C), 

 presenting somewhat elongated prism-like crystals which, upon pressure, alter 

 their form, regaining it when the pressure is removed. The same is true of 

 cholin oleate. 



These properties explain the difficulties encountered in developing sphero- 

 crystals in our earlier experiments; a slight excess of one or other con- 

 stituent of the soap or change in the relative amount of the menstruum 

 materially influences the development and appearance of the spherocrystals. 

 We are still uncertain whether pure lecithin forms spherocrystals ; it has all 

 the characters of a crystalline fluid ; but for now many months attempting 

 a great number of expedients, we have uniformly failed to develop the 

 globular anisotropous state.* 



* Here it may be laid down that the formation of myelin processes and of sphero- 

 crystals, which, it is true, often exhibited by the same substance, are not necessarily 

 correlated. A substance may show myelin forms and not be able to exhibit sphero- 

 crystals and vice versa. 



