THE KANSAS UNIVERSITY 

 SCIENCE BULLETIN. 



Vol. VII, No. 16] JUNE, 1913. K^xyfrNTie 



G^RTNERIA DELTOIDEA TORR. 



BY BERYL LOVEJOY. 

 Plates SLIII-LIV. 



THIS study, carried on in the laboratories of the Botany 

 Department of the University of Kansas, under the 

 supervision of Professor Stevens, was made from ma- 

 terial collected during the summer of 1908 by Mr. L. M. Peace, 

 on the northern slope of Tumamoc Hill, near the Desert Labo- 

 ratory at Tucson, Ariz. Here the soil is of a coarse, gravelly 

 texture, overlying caliche; and Gsertneria deltoidea, in com- 

 pany with Opvntia fulgida, are mentioned by V. M. Spaulding, 

 in his Distribution and Movement of Desert Plants, as con- 

 stituting the greater part of the vegetation of this association, 

 which is determined for the most part by soil relations. 



In the collecting of Gxrtneria, jars containing a 2 per cent 

 solution of formalin were taken by Mr. Peace into the field, 

 and the plants, as soon as gathered, were placed in these. 

 Specimens of the root, stem and leaves were obtained at two 

 different dates, the first at the beginning of the summer season 

 of rain, July 31, a later collection being made August .3. 



The genus Giertneria is described by Britton and Brown as 

 belonging to the family Ambrosiaceje (Reichenb). Gray de- 

 scribes it as "Franseria" and places it among the Compositse, 

 as does J. D. Whitney and others. 



The species deltoidea Torr. is described by J. D. Whitney 

 (1880) as being a member of the Compositse, "herbaceous, 

 with more or less woody base, low, canescent, with a fine and 



Received for publication May 24. 



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