382 The Physiology of Plants BOOK in 



refer later. Naturally so important a pronouncement was 

 followed at once by critical examination both of methods 

 and results by many inquirers. His first opponent was 

 Naegeli, who thought he saw the starch grains in process 

 of development in vacuoles in the general protoplasm, being 

 surrounded there by cell sap, at the expense of which they 

 were gradually growing. Naegeli's work appeared in 1881 ; 

 his criticisms appeared to be aimed chiefly at the view of 

 the universality of the plastid. 



In the same year there appeared the first of a series of 

 writings by A. Meyer, which are almost as noteworthy as 

 those of Schimper, of which indeed they may almost be 

 taken to be the completion. In this first memoir he con- 

 firmed Schimper's general conclusions and pointed out that 

 the starch grain grows most strongly on the side which is 

 in contact with the plastid. 



A very vigorous opposition to Schimper's position was 

 set up in 1887 by Belzung, whose work was chiefly based 

 upon certain leguminous plants. He could find no plastids 

 in the cells of the tissues of the developing embryo of 

 Lupinus albus and L. mutabilis, but saw starch was deposited 

 there. He described the cells in which its formation took 

 place as having vacuolated protoplasm, forming a network 

 with very small meshes containing only cell sap. He was 

 very emphatic in denying the presence of a plastid there, 

 and described the starch grain as originating at some point 

 of the protoplasm and growing subsequently like a crystal. 

 As a result of his researches he suggested that Schimper's 

 plastids were nothing more than cavities in the protoplasm 

 becoming filled up with starch by the action of their limiting 

 layers. In 1892 Eberdt advanced a view which differed 

 from both those quoted. He said that the growth of an 

 excentrically striated starch grain is not due to the action 

 of any unilaterally attached plastid, but that both excentric 

 and concentric grains grow in the cell sap by the action of 



