23 



lack of suitable assistance, the fact being that the personnel 

 of the department is not commensurate with the demands 

 made on it. The i)resent winter's experience has been no 

 better in spite of an earnest endeavor to take advantage of 

 our faciHties as they stand. Field methods of studying 

 transpii-ation and correlated phenomena have therefore re- 

 ceived major attention, and for this purpose I spent a 

 month, at my own charges, at the Desert Botanical Labora- 

 tory, getting data on the rate of transpiration, by com- 

 parative volumetric and gravimetric methods. It was found 

 that the discrepancy between the results obtained by these 

 methods is not fortuitous, but a regular one, the ratio be- 

 tween them reversing during night and day. The diiTer- 

 ence is believed to be due in part to the difference in the 

 water content of the leaf. Some data, obtained during 

 September and October on the cotton at Auburn, appear 

 to align themselves with this conclusion. Synchronous 

 observations on the atmometer (of Livingston), insolation- 

 thermometer, anemometer, thermometer and plant pieces 

 have also been made with the hope of elaborating field 

 methods for the comparative study of transpiration. My 

 results have been in part reported in a paper "The relation 

 of transpiration to the w^ater content of leaves," presented 

 at the recent meeting of the Botanical Society of America. 

 Mr. C. S. Ridgway has assisted me in this work. 



Some progress has been made on methods for the study 

 of the relations of fumigation to the physiological condi- 

 tion of the plant, with special reference to the condition 

 of the stomata and to the water content, but the condition 

 of the greenhouse has also interfered with this w^ork. 



The history of the pecan-scab in a single orchard, that 

 of Mr. T. W. Oliver, Montgomery, Ala., has been followed 

 with the co-operation of Mr. C. S. Ridgway, throughout 

 the year. It has come to light that the unfruitful condition 

 in this orchard is, to a large degree, not due to the pecan- 

 scab organism. A brief bulletin of information treating of 

 this organism has been published. 



The following is a list of publications from the Depart- 

 ment. 



d.) The development and nutrition of the embryo, seed 

 and carpel in the date. Phoenix dactylifera L. Ann. Rep. 

 Mo. Bot. Garden, vol. 21: pp. 103-164,4 plates. Dec. 22, 

 1910. 



(2) Guayule (Parthenium argentatum Gray) . A rubber 



