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Entered as Second-Class Matter June 12, 1909, at Sound Beach Post Office, under Act of March 3, 1897. 



Vo! 



ume 



VII 



MAY. 



Number 12 



Babcock's Walnut. 



By Robert T. Morris, M.D , 616 Madison Avenue, N Y. (Member Zinnaean Society of Na- 

 tural History). 



Some years ago there appeared upon 

 the California coast, a peculiar form of 

 walnut. It was assumed to be a cross 

 between the California black walnut 

 and the Coast live oak, and specimens 

 of this form of tree were sold in 

 America and abroad as examples of a 

 remarkable hybrid. 



Professor Ernest B. Babcock of the 

 University of California made one re- 

 port upon this form of walnut in "The 

 Journal of Heredity" for December, 

 1914. His exhaustive study of the tree 

 may well serve students engaged in re- 

 search work, as an example of accurate 

 scientific method. 



Professor Babcock came to no def- 

 inite conclusion in relation to the ori- 

 gin of this form of walnut, but he de- 

 scribes it as representing what has 

 been called "aggregate mutation, by 

 other writers. 



The study of this new walnut which 

 was named Juglans California var 

 quercina, includes investigation of 

 three chief questions: 



(1) Origin through hybridization 

 with the Coast live oak, Qucrcus (Agri- 

 folia, Nee. 



(2) Origin from teratological flow- 

 ers and fruits of Juglans Calif ornica. 



(3) Origin by mutations in appar- 

 ently normal flowers and fruits of 

 Juglans Calif ornica. 



The first question was disposed of so 

 promptly that further comment is un- 

 necessary. It is improbable that we 

 shall ever have crosses between oaks 

 and walnuts unless, at some time in the 

 future, experimenters may succeed in 

 treating the membranes of certain 

 plant cells in some such way as Loeb 

 has worked with sex cells of the star- 

 fish and the sea urchin. 



Concerning the second question, we 

 may still ask if Babcock's walnut is not 

 a teratological form. From a set of 

 abnormarnuts he obtained a larger 

 number of walnuts of this type than 

 were obtained from any nuts of appar- 

 entlv normal character from those trees 

 which furnish quercina. 



The third question leaves us asking 

 if the apparentlv normal flowers and 

 fruits of /. Califomica were always 

 quite normal. Professor Babcock as- 

 sumes the possibility of occurence of 



