The History of Plant Tissue Culture 27 



Attempts were, of course, made to duplicate 

 Carrel's and Lewis' brilliant results, with plant 

 tissues, by use of some "natural" nutrient com- 

 parable to embryo juice. All such attempts, with 

 one possible exception, have consistently failed. 

 Schmucker, in 1929, 110, reported that he had suc- 

 cessfully grown individual leaf-mesophyll cells of 

 Bocconia in a fluid prepared from a filtered ex- 

 tract of Bocconia leaves. Details were appar- 

 ently never published, the work has not been 

 verified by any later worker, and the result is so 

 at variance with all other recorded experiments 

 that its correctness is to be doubted. In the hands 

 of other workers, all preparations of tissue juices, 

 xylem sap, phloem exudate, liquid endosperm, etc., 

 have given evidence of toxicity (Prat, 1927, 451; 

 Bobbins, 1922, 177 ; Bobbins and V. B. White, 1937, 

 178* ) . This has, of course, forced workers in the 

 plant tissue culture field to resort to the much 

 more tedious, difficult, and uncertain, but at the 

 same time when successful more satisfying 

 method of developing step by step an essentially 

 synthetic medium. 



The profound influence of Haberlandt's wide 

 reputation determined the subsequent orientation 



* van Overbeek, Conklin and Blakeslee have reported successful 

 use of coconut milk as a nutrient for Datura embryos, too late for 

 the reference to be included in the bibliography of this volume. 

 (Science 94: 350-351, 1941). 



