Problem. Most studies on the selective nature of war deal with it from a eugenic point of view. The question is usually stated in some such terms as: Do certain genetic strains contribute more than their share in war? If so, and if these strains are superior, war is obviously dysgenic.1 A respectable literature has developed on this point.2 Such studies, however, usually make certain genetic assumptions. For example, it is assumed that the superiority of the men selected for service is always genetic. It is, of course, true that the flower of the land is sent to war, obvious misfits being weeded out. But to just what extent the misfits are such by genetic constitution is, on the basis of present data, indeterminable. The present study makes no assumptions about the genetic quality of the fatal casualties of war. It merely asks the question: Are certain social classes paying more for the war in terms of fatal casualties than others? The implication is that war is dysthenic if classes which would provide a more favorable environment for children contribute more to the war in terms of fatal casualties than classes which would provide a less favorable environment. The indexes of class used here are social, namely economic status as measured by median rent and education as measured by median years of schooling. Sources of Data. A list of all the fatal casualties in the city of St. Louis during the first two years of the war, December, 1942 through January 1944, was compiled from the list published in Life magazine, July 5, 1943, and the monthly reports published in the St. Louis Post-Dispatch.3 The listing was presumably complete and whatever deficiencies or incompletenesses of data there were are not, presumably, of a nature to affect the results. There is no reason to believe, that is, that the fatal casualties not reported would tend to be of any one class more than of another. For the background data to be used in analyzing these figures, the booklet Popilation and Housing4 was used. This census publication includes statistical data for census tracts in St. Louis. The background data used were: the number of men in each tract between the ages of 20 and 40, the median rent in each tract, and the median education in each tract. The reason for considering only the men between 20 and 40 is that this is the age group which is most highly represented in the armed services. The median rent used was the contract or estimated monthly rent. The median education used was that of the total population for each tract 25 years and over. Method. On a large map of St. Louis the city was divided into its 128 tracts. The addresses of the fatal casualties, determinied from the St. Louis Dispaic1' lists referred to above, were located in the tracts to which they belonged. The percentage of all the fatal casualties which were thus * This study was made in a research course under the direction of Dr. Jessie Bernard. 1 It has been argued that inasmuch as the casualties in recent wars in the United States have been relatively light, the selective nature of war, although in the direction of a dysgenic nature, is not great enough to modify the quality of the population. See W. F. Ogburn, War, Babies, and the Future (Public Affairs Pamphlet, S 83, 1943), p. 11. 2 The outstanding writer in this field is D. S. Jordan. See his War and the Breed (1915). I We would like to thank the St. Loutis Post-Dispatch for their kind cooperation in this connection. 4 Population and Houising, Statistics for Census Tracts, St. Louis, Mo. and Adjacent Area, Prepated under the Supervision of Dr. Leon E. Truesdell, Chief Statistician for Population (United States Government Printing Office, Washington, D. C., 1942).