Number of brooded eggs and wet and dry brood weights were measured in the estuarine crab, Chasmagnathus granulatus. Best correlations for all reproductive variables were found with respect to female wet body weight, but while the best fitted model was logarithmic for broods having uneyed embryos (UE), a linear model corresponded to eyed embryo (EE) broods. For UE, larger females invested in each brooded egg 8.4% more of dry biomass than smaller females, in accordance with the logarithmic model adjusted. Overall fecundity was estimated in 26790±9936 eggs/brood/female. Biomass investment in reproduction was estimated in 7.1 % (dry weight basis) and 9.3% (wet weigh basis). Egg dry weight decreased throughout embryonic development, in accordance with metabolic requirements of embryos, while a higher water content was noted in EE, probably related to tissue solvation during development and/or increase of the osmotic pressure needed for hatching.

Whole body oxygen consumption and some hemolymph parameters such as pH, partial pressure of gases, level of ions and lactate were measured in the estuarine crab Chasmagnathus granulata after both acute (96 h) and chronic (2 weeks) exposure to cadmium at concentrations ranging from 0.4 to 6.3 mg/l. In all instances, the crabs developed hemolymph acidosis, but no respiratory (increased P CO 2 ) or lactate increases were evident. Hemolymph levels of sodium and calcium were always increased by cadmium exposure. The chronic toxicity of cadmium was enhanced at 12 salinity, even causing a significantly higher mortality in comparison with the higher salinity (30) used. A general metabolic arrest took place at 12 salinity in the crabs chronically exposed to cadmium, as indicated by decreases of oxygen consumption and P CO 2 , an increase of P O 2 , along with no changes in lactate levels. These imbalances were associated with severe necrosis and telangiectasia in the respiratory gills, probably leading to respiratory impairment and finally histotoxic hypoxia and death of the animals. Correspondence

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