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A TRICOTYLEDONOUS 15EAN. 



J. M. Van Hook. 



While oxamining a number of Lima hean seed in the sumnifr of IJti'O. tlie 

 writer was surprised to find between the ordinary cotyledons a third body, 

 apparently a third cotyledon. Its shape and location is well shown in the 

 accompanying figure. While a greater portion of the extra cotyledon lies 

 parallel with the others and pressed between them, the part at the end 

 where it is attached is twisted so that it is vertical to its flat surface and 

 lies beween the plumule and radicle. The two roguliir cotyledons arc also 

 attached at this end. 



Enlarged tricotyledonous bean with one of the outer potyledons removed. 

 Polycotyledouous beans may not be of rare occurrence, though the writer 

 knows of none reported on Lima beans. Harris (Mem. X. Y. Bot. Gard. 

 1916.) reports a race of the common bean which has tlie cotyledons varying 

 from two to seven in number, but which tends to be tetracotyledonons. 

 Indiana University, 

 October, 1920. 



