1. A circulatory rating test was used during the war to aid in detecting aviators who were unstable, and therefore were not in condition to fly at that time.2. In applying this test to a group of psychotic cases it was found that 82.61 per cent of the hebephrenic and catatonic types of dementia præcox patients rated low and that only 26.9 per cent of the paranoid types of dementia præcox rated low. Also only 11.2 per cent of the manic depressive patients rated low.3. In 4800 necropsies reported by Lewis (3) he found that 71.55 per cent of the hebephrenic and catatonic types of dementia præcox had a small aplastic heart, the incomplete development involving also the capillary system. Furthermore 75.5 per cent of these cases had hearts of less than average weight, while only 7.8 per cent of the paranoid dementia præcox had hearts of less than average weight.4. The circulatory rating test was revised by me so that it could be applied on adolescent children between the ages of 10 and 15 years.5. The revised test was applied to 100 adolescent children in the public schools of the District of Columbia, all of whom were in the same grade but in three different groups, having been rated by a psychological test and placed accordingly.6. Out of the 1OO children rated by my revised circulatory test, 26 were in the advanced class, and four of these, or an average of 15.3 per cent, rated below 10. Forty-five pupils were in the middle class and four of these, or an average of 8.9 per cent, rated below 10 points; and finally 29 pupils were in the retarded class, and seven of these, or an average of 24.4 per cent, rated below 10 points. This showing that the more or less stable middle class had the smallest average of pupils rating below 10 points.7. When this list of 15 pupils, who had a low rating was presented to the principal of the school she stated that all of them were problem children, and the histories obtained from both the teachers and the pupils showed many neurotic symptoms.8. The revised test was performed on 100 adolescent feeble-minded children in the Waverley School for Feeble-Minded and only two pupils graded below 10 points. One of these pupils had an organic heart disease, both were of the familial type of feeble-minded, and neither was syphilitic.9. As a group, the mental defects graded high in the circulatory rating test.10. In reading the literature on the pathology of the mental-defect one finds very little concerning the cardio-vascular system.11. The circulatory test seems a valuable instrument for detecting a certain special type of individual. Eighty-two and sixty-one-hundreds per cent of the hebephrenic and catatonic dementia præcox type rated low. The 15 per cent of the public school children who had neurotic symptoms rated low. While practically none of the adolescent feeble-minded children graded low.