28 Plant Tissue Culture 



of the majority of investigations concerned with 

 the cultivation of plant tissues for a quarter of a 

 century and, while animal tissue culture studies 

 were making rapid strides, plant studies were for 

 the most part wandering in what we now look 

 upon as blind alleys. Smith in 1907, 325, Bobilioff- 

 Preisser in 1917, 90, Lamprecht in 1918, 102, 103, 

 Thielman in 1924, 111, and 1925, 112, 113, Borger, 

 92, and Czech, 93, in 1926, Kunkel, 101, and Prat, 

 451, in 1927, tJlehla, 115, and Kemmer, 99, in 1928, 

 Pfeiffer, 107, and Scheitterer, 109, in 1931, five of 

 them students of Haberlandt, all attempted to grow 

 cells of mature type. The materials studied in- 

 cluded leaf fragments of Peperomia, Bryophyllum, 

 Kalanchoe, Crassula, Sempervivum, Allium, Poly- 

 podium, Aspidium, Dicranum, Begonia, Triticum, 

 Pisum, Tradescantia, etc., epidermis of Viola, 

 Thunbergia, Rlioeo, stem tissues of Solanum, Bras- 

 sica, Saintpaulia, Coleus, Daucus, young ovaries 

 of Cucurbita, pith cells of Symphoricarpus, and a 

 variety of other plant parts. All gave equally 

 unsatisfactory results. Kiister, in 1928, 20, con- 

 sidered the problem hopeless ("aussichtslos") 

 and asked if perhaps the assumption that cells are 

 totipotent might not itself be false. There was, 

 indeed, much evidence from a variety of sources 

 which appeared to be contrary to this assumption. 

 Not the least indicative of these evidences came 



