In mammals, maternal expenditure on offspring is a complex mix of several factors including the species' mating system, offspring sex and the condition and age of the mother. While theory suggests that in polygynous species mothers should wean larger male offspring than females when resources and maternal conditions allow, the evidence for this remains equivocal. Southern elephant seals are highly dimorphic, polygynous capital breeders existing in an environment with highly variable resources and should therefore provide clear evidence to support the theoretical expectations of differential maternal expenditure in male and female pups. We quantified maternal size (mass and length) and pup size at birth and weaning for 342 elephant seal mothers at Macquarie Island. The study was conducted over 11 years of contrasting sea-ice and Southern Annular Mode values, both indices of maternal prey resources. Overall, large females weaned male pups that weighed 17 kg (15·5%) more than female pups. Maternal condition varied by as much as 59 kg among years, and was positively related to Southern Annular Mode, and negatively to maximum sea-ice extent. Smaller mothers weaned relatively larger male pups under favourable conditions, this effect was less apparent for larger mothers. We developed a simple model linking environmental variation to maternal masses post-partum, followed by maternal masses post-partum to weaning masses and then weaning masses to pup survival and demonstrated that environmental conditions affected predicted survival so that the pups of small mothers had an estimated 7% increase in first year survival in 'good' vs. 'bad' years compared to 1% for female pups of large mothers. Co-occurrence of environmental quality and conservative reproductive tactics suggests that mothers retain substantial plasticity in maternal care, enhancing their lifetime reproductive success by adjusting reproductive expenditure relative to both prevailing environmental conditions and their own capabilities.

4s yet no method of ureterocolic anastomosis has proved its superiority in a large series of cases, and the operation still carries a not inconsiderable morbidity and mortality rate. The evolution of an improved technique is hindered by difficulty in investigating the causes of failure as the clinical manifestations of failure due to all causes are those of local or spreading inflammation and ureteral obstruction. Post-mortem examination is often not possible until a time when precise evidence of the cause of failure is lost in suppuration.Most methods of ureterocolic anastomosis involve the isolation of 5 to 6 cm. of ureter, and although the risk of ischsmic necrosis of this portion of ureter has been widely recognised (Nitch, 1932 ; Flocks, 1947 ;Cordonnier, 1949), there have been few assessments of the importance of this danger. Harper (1942) concluded that division of the lower ureteral twigs from the inferior vesical and middle rectal arteries would not produce ischlemia and impaired vitality of the duct,

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SUMMARY Intravenous injections of 65Zn containing 50 to 100 μc. of radioactivity and 50 to 100 μg. of carrier zinc have been given to fifteen patients suffering from various forms of malignant disease and the radioactive content of blood and other tissues estimated twenty to ninety‐six hours later. Results expressed as 65Zn organ/blood ratios have been compared with zinc organ/blood ratios calculated from data reported by other workers from chemical determinations on similar tissues. The radioactive and chemical ratios are generally of the same order with the exception of muscle which had a much lower, and liver and certain samples of carcinomatous prostatic tissue which had a much higher 65Zn ratio than Zn ratio. Carcinomatous prostatic tissue from one patient had a 65Zn tissue/blood ratio of 40, which is twice as much as the highest ratio found in any other tissue. This study was supported by the New York Cancer Committee and the Lerner Fund. The writers gratefully acknowledge the assistance of Miss Eva Simmel in preparing the autoradiographs.