Land crabs produce isosmotic urine but reduce salt loss by reabsorbing salt via the gills to produce a dilute excretory fluid (P). This branchial salt reclamation is regulated in response to changes in dietary salt availability. The regulation of branchial Na reabsorption and osmotic status was investigated in the terrestrial crab Gecarcoidea natalis on Christmas Island. Confinement within fiel...

Waterborne zinc (Zn) is known to cause toxicity to freshwater animals primarily by disrupting calcium (Ca) homeostasis during acute exposure, but its effects in marine and estuarine animals are not well characterized. The present study investigated the effects of salinity on short-term Zn accumulation and sub-lethal toxicity in the euryhaline green shore crab, Carcinus maenas. The kinetic and p...

The Nkx2.6 gene belongs to the NK superfamily of homeobox genes (Harvey, 1996). We report here the expression pattern of the murine Nkx2.6 gene during early mouse development, which is unique among the NK family of homeobox genes in that its expression is restricted to the very narrow development period between stages E8.5 and E10.5 of embryogenesis. The distribution of Nkx2.6 transcripts is al...

The afferent pathways mediating cardiovascular and ventilatory hypoxic reflexes were identified in anaesthetized, spontaneously breathing (ASB) channel catfish, Ictalurus pimctatus (Rafinesque), by bilateral section of cranial nerve IX and branchial branches of cranial nerve X to the four gill arches (Xbi-Xb4). Cardiovascular and ventilatory responses to hypoxia and NaCN were attenuated by part...

JJ-, a fairly healthy lad of 19, was attacked by pneumonia during last summer, from which he made a rapid recovery. Whilst attending him I noticed a small opening on the right side of his neck, large enough to admit a fine probe. A little u^uco-purulent fluid exuded from it, especially if slight pressure Was applied on the side nearer the head. The orifice was seen to be the termination of a tu...