188 EEPORT OF OFFICE OF EXPEEIMENT STATIONS. 



making certain improvements in the accessory parts of the respiration 

 calorimeter, inchicling especially electric parts of a new combustion 

 furnace and improvements in devices for sampling the air current 

 and for measuring separately the heat and carbon dioxid produced 

 while the animal is lying and standing in the respiration chamber. 



During the year progress was made in bringing up the arrears of 

 computation upon previous work. Discussion of the results of the 

 experiments made in the years 1904—1907 was completed and the full 

 report upon them was published as a supplement to the annual report 

 of the experiment station for 1910-11, under the title of " Influence 

 of Type and of Age upon the Utilization of Feed by Cattle," and 

 also as Bulletin 128 of the Bureau of Animal Industry of this 

 department. During the year bulletins were also prepared upon 

 " The Nutritive Value of the Nonprotein in Feeding Stuffs " and 

 upon " The Maintenance Requirements of Farm Animals," both 

 including a full review of the literature, and published as Bulletins 

 139 and 143 of the Bureau of Animal Industry. Two papers were 

 also prepared for the Second International Congress of Alimentary 

 Hygiene and of the Rational Feeding of Man, at the request of the 

 American committee, viz, " Influence of Type and of Age upon the 

 Utilization of Feed by Cattle," containing a summar}^ of the more 

 important points of the full report upon the same subject, and " The 

 Respiration Calorimeter at the Institute of Animal Nutrition of the 

 Pennsylvania State College." These papers have also been published 

 as Bulletins 104 and 105 of the experiment station. The cooperation 

 with this department was continued during the year. 



PORTO RICO. 



Porto Rico Agricultural Experiment Station, Mnyaguez. 



Under the supervision of A. C. True, Director. Office of Experiment Stations, 

 United States Department of Agriculture. 



D. W. May, M. Agr., Special Agent in Charge. 



The work of the Porto Rico station during the year was continued 

 along the well-planned lines previously described. Only few changes 

 were made in the personnel of the station staff. The coffee investi- 

 gations carried on for nearly 10 years on the Carmelita plantation 

 were brought to a close and the work was transferred nearer to the 

 station. The low portions of the fields were drained with earthen 

 tile made on the premises and a machine was purchased for the manu- 

 facture of cement tile to facilitate future work of this kind. 



In the act of Congress making appropriations for the station for 

 the fiscal year, special provisions were made for coffee investigations. 

 A 95-acre coffee plantation was placed at the disposal of the station 

 for experiments in renovating an old plantation and for studies on 



