344 



SCIENCE 



[N. S. Vol. LIII. No. 1371 



Geometrical development of analytical ideas: Pro- 

 PESSOE L. C. Kakpinski, University of Michi- 

 gan. 



The anharmonic ratio in projective geometry : Peo- 

 PESSOE E. B. Stodpfeb, University of Kansas. 



The association's ideal for expository papers: Peo- 

 PESSOE E. J. WiLCZYNSKi. (Introductory Note.) 



The first work on mathematics printed in the new 

 world: Peopessor David Eugene Smith, Co- 

 lumbia University. 



Belle's theorem and its generalizations: Peo- 

 PESSOE A. J. Kempnee, University of Illinois. 



Some geometrical aspects of the theory of relativ- 

 ity: Peopessor L. W. Dowling, University of 

 Wisconsin. 



Note on "the metric question from the historical 

 standpoint" : Peopessoe L. C. Kaepinski, Uni- 

 versity of Michigan. 



General aspects of the problem of interpolation: 

 Peopessoe Dunham Jackson, University of 

 Minnesota. 



Construction of double entry tables: Peopessoe 

 A. A. Bennett, in charge of the U. 8. Ordnance 

 Ballistic Station, Baltimore, Md. 



Certain general properties of functions : Peopessor 

 Henry Blumbeeg, University of Illinois. 



In addition to the election of Professor G. A. 

 Miller as president of the Mathematical Associa- 

 tion of America, the following elections were 

 made: 



For Vice-president: E. C. Archibald, Brown 

 University; R. D. Carmichael, University of Illi- 

 nois. 



For Members of the Board of Trustees: A. A. 

 Bennett, U. S. Ordnance Ballistic Station; Florian 

 Cajori, University of Oalifornia; H. L. Eietz, 

 University of Iowa; D. E. Smith, Columbia Uni- 

 versity; C. P. Gummer, Queen's University. 



Seventy-two individuals and three institutions 

 were elected to member^ip and a Texas Section of 

 the association was approved. 



Wm. H. Eoevee, 

 Secretary, Section A; 



Aenold Dresden, 

 Secretary, American Mathematical Society, 

 Chicago Section; 



W. D. Caiens, 

 Secretary, Mathematical Association of 

 America 



THE AMERICAN SOCIETY OF 

 AGRONOMY 



The winter meeting of the society was held at 

 Chicago in afSliation with the American Associa- 

 tion for the Advancement of Science, on Friday, 

 December 31. 



The program follows: 



symposium 



Our Present Knowledge of Methods of Corn 



Breeding 



Leader: H. K. Hayes, University of Minnesota, 

 St. Paul, Minn. 



The experimental basis for the present status of 

 corn breeding: F. D. Eichey. A review of experi- 

 mental efforts to increase corn yields by breeding 

 points to the foUowing conclusions: (1) Mass se- 

 lection on the basis of production of mature, sound 

 grain per plant, under conditions of uniform 

 stand and fertility, may be recommended as a 

 means of at least maintaining yields. (2) There 

 is no evidence that ear-to-row breeding can be re- 

 lied upon to obtain increased yields commensurate 

 with the cost. (3) First generation varietal 

 crosses, and crosses or double crosses between 

 pure lines, offer possibilities for obtaining larger 

 yields; but the value of each combination must be 

 determined experimentally. (4) The evidence as a 

 whole shows clearly the value of selection in ob- 

 taining better adaptation to a specific environ- 

 ment and the value of hybrid vigor in obtaining 

 larger yields. These principles, in connection with 

 the Mendelian interpretation of heterosis as due to 

 linked dominant growth factors, point to selection, 

 hybridization, and further selection, all based on 

 pure lines and controlled pollination, as the only 

 sound basis for real corn improvement. 



The bearing of modern genetic studies on corn 

 breeding: E. A. Emerson. 



Corn breeding as a hobby: H. A. Wallace. 

 Eight rather late corn varieties were combined as 

 pollinating parents with each of twenty rather 

 early mother parents. Of these 160 combinations, 

 50 were tried out in comparison vrith the Iowa 

 Station strain of Eeids at Ames and the others 

 were tried out at Des Moines. At both places a 

 strain of Eeids known as Iowa 10 proved to be the 

 best of the eight as a pollinating parent and a 

 Kentucky strain of Johnson Co. White proved to 

 be poorest. During 1916, 1917, 1918 and 1919, the 

 Iowa Station has tried out 287 hybrids and of 

 these only 50 have outyielded the station strain of 

 Eeids. There is probably about one chance in one 

 hundred of finding a cross of two distinct varieties 

 which will prove to be an improvement on the best 

 of the varieties now in use. The most promising 

 cross so far discovered in Iowa is a cross of the 

 Iowa Station strain of Eeids with Argentine corn. 



The author believes that there must eventually 

 be special purpose corns such as 90-day corns, 

 silage corns, etc., as well as standard grain vari- 



