

DEVELOPMENT AND NUTRITION OF THE EMBRYO, 



SEED AND CARPEL IN THE DATE, PHOENIX 



DACTYLIFERA L. 



BY FRANCIS E. LLOYD. 



PURPOSE AND SCOPE OF THE STUDY. 



The work here reported was begun in 1907 upon my 

 appointment as Cytologist to the Agricultural Experiment 

 Station, Tucson, Ariz., in connection with the special investi- 

 gations on the date which have there been carried forward 

 during recent years, more especially by Dr. A. E. Vinson. 

 The material was collected, through the co-operation of Dr. 

 Vinson, at the Station Date Orchard, at Tempe, Ariz. At 

 the inception of the work it was my purpose to study 

 exhaustively the whole period of embryogeny with reference 

 to the role of the various foods and other materials in the 

 seed and carpel, and for this purpose, it would have been 

 necessary to make use of both preserved and fresh material. 

 This object was defeated by my removal to Mexico, and I 

 was therefore compelled to make use exclusively of preserved 

 material, with the exception of some of the earlier stages 

 which I studied before leaving Tucson. In consequence, the 

 sugars have, I regret, been left out of account. This is of 

 less consequence as regards the carpel, as they have been 

 studied, by the methods of the chemical laboratory however, 

 by Dr. Vinson, who has embodied his results in various 

 papers to be later referred to. The present paper records 

 my studies therefore of the anatomy and histology of both 

 seed and carpel from the developmental point of view, and 

 of the roles of tannin, starch, oil and reserve cellulose. Mate- 

 rial of two well marked races, Rhars and Deglet Noor, invert 

 and cane sugar types, 1 respectively, has been examined, but 

 it has developed that such differences as exist are, from the 

 present point of view, negligible. When desirable, I have 



noted such differences. 



Vinson, 1906. 



(103) 



