A COMPARATIVE STUDY OF LASAEA AUSTRALIS, VULSELLA SPONGIARUM, PINNA BICOLOR AND DONACILLA CUNEATA (MOLLUSCA; BIVALVIA) FROM PRINCESS ROYAL HARBOUR, WESTERN AUSTRALIA

Monthly samples of L. australis, V. spongiartum, P. bicolorand D. cuneata were collected over a period of 12 months fromPrincess Royal Harbour, Western Australia. Preliminary informationon densities and biomass is given. Gonad histology points toseasonal reproductive cycles with autumn spawning in P. bicolorand D. cuneata and irregular spawning in V. spongiantm and L.australis. However, L. australis did show two peaks of larvalbrooding in the study period. Length-frequency data are discussedin the light of the proposed reproductive patterns for the fourspecies. Allometric relationships between length and both heightand width for all species are described and their value to eachspecies assessed. Populations of L. australis from differenthabitats show significant differences in shell shape. (Received 27 June 1983;