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ions, which rapidly solidified to solid spherolite crystals. In the ease 

 of this compound also, one feels convinced that there must exist a 

 very intimate relation between the spherolite-formation of a substance 

 and its power of forming anisotropous liquid phases; on the nature 

 of this relation, T hope to make a communication later on. 



It may, however, be observed, provisionally that in all trans- 

 formations: liquid ^ solid, where serious "phenomena of retardation" 

 may occur, the undercooling, or superfusion, for instance is generally 

 abrogated amid a differentiation of the phase into spherolites. All 

 the cholesterol-derivatives, mentioned in this paper, exhibit this sphe- 

 rolite-formation. In the ease of a-phytosterol-propionate, I have been 

 able to show, that a complex of a large number of doubly -refracting 

 microscopic spherolites may imitate the optical peculiarities of the 

 liquid phases in process of separation and of the colloidal opalescence. 

 This might lead to the strengthening of the previous conception of 

 the colloidal solidification as a separation-phenomenon of labile liquids. 



§ 13. Choleste?'ol-Heptylate contains only labile liquid anisotropous 

 phases. It exhibits great similarity with the caprylate described previ- 

 ously : I have only a few times been able to obtain one single thick- 

 fluid phase A from the undereooled isotropous fusion L. The solid 

 phase crystallises rapidly and in beautiful flat needles, which exhibit 

 high interference colours. On warming, the substance readily migrates 

 towards the colder parts of the object glass. 



§ 14. In conclusion, I will communicate a few more points as 

 regards some phenomena, which prove plainly the significance of 

 the spherolite structure for with these questions. 



Some time ago, I published a research on the fatty esters from 

 Phytosterol from Calabar-fat and stated how they all are wont to 

 crystallise in the spherolite-form from their cooled, isotropous fused 

 mass, while anisotropous liquid phases are not observed therein, with 

 the exception of the normal valerate which possesses a thick-fluid 

 anisotropous modification, and exhibits the phenomenon of the chang- 

 eable melting point, which again becomes normal on long keeping; 

 a fact also observed in the case of a few fatty glycerol-esters. Since 

 then, Windaus has proved that the phytosterol, extracted from Calabar 

 fat is a mixture of two isomorphous phytosterols, which cannot be 

 separated by crystallisation. Being engaged in preparing the pure 

 fatty esters from the principal of those two phytosterols, namely 

 the «-compound (m.p. 136°), 1 discovered that the fused propionate 

 of a-phytosterol (m.p. 108°), when cooled rapidly in cold water, 



