32 The various changesgenerally associated with physiological senescence are known to show wide variability amongindividuals of the same age, and this was borne out by these data. However, some of the criteria appeared to be better indices of aging than others, judging by the degree of change and the variability of the data observed. (This statement is not based on statistical analysis.) Someof the better criteria appeared to be accommodation of the eyes, visual acuity, skin retraction, arcus senilis, greying of the hair, and hand strength. The measured criteria would be expected to be morereliable than the estimated ones in view of the subjective element and less precise Table 20 Subject No. Sex 17 F 24 F 26 M F 49 F 59 F 63 F 67 F ness, but, since loss of subcutaneousfat is some- what age dependent, probably in the right direction. It is hoped that in the future statistical treatmentof the data mayfurnish a weightingfactorfor each criterion based on the degree of age-associated change andthevariability of the data. It is not always possible to run the complete battery of tests on each individual, and use of such weighting factors would tend to minimize the disparity due to the omissions. - The data presented must be consideredas preliminary in nature and to represent only a small Residual Beta Burns, 1960 fraction of the many varied changes associated Age examinations of the Marshallese, the batteryof with the aging process. Underthe conditions of Description 9 Slight depigmentedscars, left ante- cubitalfossae. 19 Mottled spots of pigmentation and depigmentation, dorsum offeet. 18 Marked scarring between first and second toes, right foot, with binding to subcutaneoustissues. Areas oflesser involvement peripheral to this area. No evidence of chronic radia- * 39 scoring of the latter. This appeared generally to be the case, but the estimated values for greying of the hair and arcussenilis correlated surprisingly well with age. The amountof subcutaneousfat probably influenced measurements of skin loose- tion dermatitis. 20 Sight mottled pigmentation-depigmentation with little scarring, dorsum offeet. Mottled hyperpigmented spots persist on back of neck. 21 Black moles believed to have in- tests employedis necessarily limited. As more experience is gained, someofthe tests may be elimi- nated and new ones added. Thetests of vigor are thought to be extremely important in assessing aging, andit is hoped that moretests of this nature may be added. At this time the data are presented to introduce an approach to a feasible meansof assaying “biolocical age” which might be ofuse in studying the possible effects of radiation on the aging phenomenon in humanbeings. In the case of the exposed Marshallese, results of further aging surveys will be carefully evaluated. and the results creased in numberoverright side of neck, also several noted in left antecubital fossa. 40 Mottled roughening and pigment variation, back of neck. 42 Mottled pigmentation, left side of neck, with slight rougheningofskin. 20 Depigmented scarred areas with slight atrophyof skin over dorsum of feet, particularly at site of deeper scar onleft foot. Some areas adjacent 78 79 F M to scars show increased pigmentation. 43 Pigmented moles appear to havein- creased in numberoverleft side of neck and to lesser extent on right side at sites of rather deep beta burns. 45 Back of ieft ear shows depigmented scar with some binding downto cartilage. No evidence of breakdown. Figure 32. Residual scarring between first and second toes, right foot, from beta burns, 5 years post exposure (Subject #26).