8o IMBIBITION AND MOLECULAR STRUCTURE 



probably the case with the cell-wall and starch-grains. Indeed Nageli first 

 based his micellar hypothesis upon observations made upon starch-grains, 

 cell-walls and crystalloids, and only later extended this view to the proto- 

 plasm itself, in which the character and mode of arrangement of the micellae 

 and micellar complexes are especially varied and complicated. 



The micellar theory enables us to refer all physiological processes to 

 the domain of molecular phenomena. It is true that all such reasoning is 

 of a speculative and hypothetical character, but nevertheless a clear grasp 

 of the principles of the micellar hypothesis is of great importance, although 

 we may be as yet unable to explain physiological phenomena by direct 

 reference to the form, structure, composition and relationships of the 

 component parts of the living organism. Not only is this the case with 

 regard to the living protoplast, but the same also applies to dead organic 

 structures as well. Thus when a dead cell-wall swells in one case more 

 markedly in one direction than in another, but in another case equally 

 in all directions, we do not know whether the peculiarity is due to a different 

 shape of the component micellae or to a difference in the way in whch they 

 are arranged. 



Crystals capable of Imbibition (Crystalloids] '. If ordinary crystals are assumed 

 to be built up of crystalline particles, it must also be admitted that the component 

 particles of crystalloids are regularly arranged. Since it has been found possible to 

 obtain the crystalloid proteids in crystalline form outside of the organism, there 

 can be no doubt that these crystalloids are formed, and grow, within a living 

 cell in exactly the same manner as they do in the external world. It belongs 

 therefore to the science of Crystallography to study and explain the structure and 

 properties of crystalloids. The degree of swelling of which a regular crystalloid is 

 capable is constant along the different axes, but different in the different kinds of 

 crystals. 



Starch-grains". The mode of swelling and the optical phenomena exhibited 

 by starch-grains indicate that the grain is built up of crystalline and anisotropous 

 elements having their longer axes arranged radially. According to Nageli, these 

 are crystalline micellae, according to Schimper, and Meyer, minute crystals 

 (Trichites). In both cases, the existence of minute crystalline elements is assumed. 

 Schimper and Meyer, however, use the term sphaerocrystal more generally, and apply 

 it also to those cases in which the component crystalline elements are so small as 



' Nageli, Bot. Mitth., 1862, Bd. i, p. 217 ; Schimper, Unters. iiber d. Protein-krystalloide, 1873 ; 

 Lehmann, Molecularphysik, 1888, Bd. I, p. 550. On the artificial formation of crystalloids, see 

 Griibler, Uber krys. Eiweiss d. Kurbissamens, 1881 ; Drechsel, Journal f. prakt. Chemie, 1879, Bd. 

 XIX, p. 331; Ritthausen, I.e., 1882, Bd. XXV, p. 150. nnd the literature there quoted. See also 

 Schimper, Bot. Zeitung, 1883, p. 152. 



a Nageli, Die Starkekorner, 1858; Bot. Zeitung, 1881, p. 63 2 Schimper, Bot. Zeitung, 1881, 

 p. 233; A. Meyer, Unters. iiber Starkekorner, i?9?, pp. 116. &c., and the literature cited by Meyer 

 in Bot. Zeitung, 1896. p. 330. 



