AGEICULTURE AT THE AMEEICAN ASSOCIATION. 539 



tioii, iuid those injui'ious to mankind In* carrvino- diseases. A study of 

 the life liistorv of these insects is made for the purpose of revealing 

 their most \ulnerable points, and then attacks upon them are made at 

 those points. This method has enabled the Division of Entomology 

 among other things, to check the ravages of the cotton-boll weevil 

 b\' cidtui'al methods, and to point out ways of lessening the ravages of 

 the codling moth in the Northwest. The Division has also introduced 

 into this country a number of l^eneficial insects, such as the ladybird 

 beetle from Australia, which has saved the orange crop of California, 

 and the insect from Algeria which fertilizes the Smyrna fig and makes 

 it possible to successfully grow this fruit in California. 



PHYSIOLOGY. 



A number of papers of especial interest to students of nutrition 

 were presented at the meetings of the American Physiological Societ}". 

 Among these the following may be mentioned: New Experiments on 

 the Physiological Action of the Proteoses, by L, B. Mendel and F. B. 

 Underhill; Further Observations of the Movements of the Stomach 

 and Intestines (with demonstration), by W. B. Cannon; Salivary 

 Digestion in the Stomach, by W. B. Cannon and H. F. Day; Biological 

 Relationship of Proteids and Proteid Assimilation, l)y P. A. Levene 

 and L. B. Stookey; On Digestion of Gelatin, by P. A. Levene and 

 L. B. Stookey; On the Nucleoproteids of the Pancreas and Thymus, 

 with Special Reference to their Optical Properties, by A. Gamgee and 

 W. Jones. Professor W. O. Atwater read a paper on the Sources of 

 Muscular P^nergy, in which the results of his experiments with the 

 respiration calorimeter were quoted with especial reference to the 

 value of different materials as sources of energy in the animal body. 



ENGINEERING. 



A paper on Agricultural Engineering, by Elwood Mead, noted the 

 revolution in the conditions of farm life and farm labor in the last fifty 

 years. These have necessitated greater attention on the part of the 

 farmer to problems in agricultural engineering, the substitution of 

 power for hand labor, and the use of more effective implements and 

 machines. A nmnberof the agricultural colleges of this country have 

 turned their attention to this matter, incorporating in their courses 

 of instruction a study of the principles on which efficient machines 

 rest ; and in European countries institutions have been established for 

 the study and improvement of farm machinery, which are supported 

 by the State. The lack of classified and verified information was men- 

 tioned; and the desirability of efforts in this direction by the National 

 Department of Agriculture was pointed out. 



C. G. Elliott described The Drainage Problems of Irrigation, a new 

 series of problems which confront the owners of irrigated lands. The 



