ESTIMATION OF AGE AND GROWTH IN THE ST-JOSEPH CALLORHINCHUS-CAPENSIS (DUMERIL)

Age and growth of Callorhinchus capensis (Order Chimaeriformes) are es timated from counts of serially deposited cones of dentine in the dors al spine. Age estimates are validated by cone margin characteristics. Growth curves for females and males are described by the formulae L(t) = 1 089,375(1-e0,0515(t+0,606))0,520 and L(t) = 685,641(1-e0,171(t+0, 721))0,593 respectively. The relationship between spine length and age for both sexes combined is described by the equation S(t) = 162,594(1 -e-0,254(t+1,434)). Age to mass relationships differ greatly between s exes and are best described by a Von Bertalanffy curve for males, M(t) = 2,155(1-e-0,483(t+13,131)), and a linear relationship for females, M(t) = 0,399(t+0,098). The relatively greater mass of older females re flects a large increase in female girth following the onset of sexual maturity.