Numerous studies have assessed side dominance assuming arm bones on the side of handedness will be larger, but concerns over sample size or replicability of measurements usually emerged. Attempting to improve upon these limitations, this investigation analyzes patterns of side difference for standard length and transverse dimensions of the scapula, clavicle, humerus, ulna, and radius for 137 individuals of known handedness. The results showed that with few exceptions, the right side of the skeleton was consistently larger in most individuals regardless of side dominance. Combinations of other measurements previously suggested to be indicative of handedness as well as the use of discriminant analysis also failed to provide reliable estimators. These findings are likely related to the fact that activities of modern individuals are generally not sufficiently unilateral in their stresses to cause asymmetrical development in the arm bones. Therefore, it is recommended that other means be developed to assess side dominance.

SummaryThe histopathology of the skin in hypotrichosis has been studied for a Jersey calf and comparisons made with normal skin. Other abnormalities of the hair follicle have been described in a Hereford mutant.There is considerable variation in hypotrichosis of the calf, as in mice, all forms involving retardation or arrest of the prenatal and early postnatal skin development.A feature of the skin in hypotrichosis is a high concentration of abnormally complex arteriovenous anastomoses. It is postulated that this abnormality of cutaneous vascular supply is a predisposing factor in the development of the syndrome. The poor development of the hair follicles and associated sweat glands appears to result from insufficiency of the capillary bed. An analogous situation in humans is cutaneous necrosis of the leg as a result of dilatation of the arteriovenous anastomoses.While arteriovenous anastomoses do not appear compensatory to lack of sweat glands, they do provide an alternative thermoregulatory mechanism which might be effective at moderate environmental temperature.