Observations on the Morphology of the Mantle Folds of the Pediveliger ofOstrea EdulisL. and their Function During Settlement

Abstract

Stafford (1913) rejected the view of many early workers (see Ryder, 1883, 1884; Huxley, 1883; Horst, 1886) that oyster larvae cemented themselves to the substratum with secretions of the mantle edge. He thought that the mantle margin could not be extended sufficiently to form the extensive area of cement that he found on the left valve of cemented larvae. Furthermore, he argued that the mantle could not secrete so much material in the short period that larvae took to cement. He deduced from the much reduced state of the ‘byssus gland’ in settled larvae that this gland was the source of the cement and suggested that the cement was spread over the shell by the foot. Nelson (1924), Prytherch (1934), Cole & Knight-Jones (1939) and Cranfield (19736, c) have clarified the role of the foot in cementing. Nelson (1924) also noted that cementing oyster larvae extended the mantle margin over the substratum but considered that this action spread the cement discharged by the foot and that the folds themselves did not secrete more material. The other authors, like Stafford, have dismissed or ignored any part the mantle folds might play in cementing.

Acquisition of particle processing capability in the oyster Crassostrea gigas: ontogeny of the mantle pseudofeces rejection tracts

“…The presence of a larval oyster mantle marginal rejection tract has heretofore either not been reported or explicitly refuted (Yonge 1926). The first report of a marginal ciliated band in larval oysters was that of Cranfield (1974), later confirmed by Waller (1981), in Ostrea edulis; the possible connection to the process of pseudofeces rejection was not explored in these studies. The ventralward beat of the component cilia, observed in the present study, would prevent particles rejected in the buccal region from re-entry into the pallial cavity.…”

Treatise Online no. 45: Part N, Revised, Volume 1, Chapter 21: Cementing Bivalvia

“…Although early cementation in larval oysters may be effected by a cement derived from the byssal glands (cranfiEld, 1973a(cranfiEld, , 1973b(cranfiEld, , 1973c, that of larger individuals can only be achieved by the mantle lobes, and therefore, by modification of the normal shell-secretion mechanisms (cranfiEld, 1974;YongE, 1979;harpEr, 1992). A key adaptation in this respect is that the shell must be applied directly to the substrate.…”

Larval Colonizing Strategies in Marine Benthic Invertebrates

“…This suggests that variation within species in larval features along clines may occur. Variation between species reflecting possible differences in energy allocation includes loss of the velum in some larvae subject to delay in metamorphosis and not in others (Culliney, 1974), Placopecten magellanicus losing the velum but not Mytilus edulis: variation in size at which the pediveliger foot is active between Modiolus rnodiolus and Mytilus edulis (de Schweinitz and Lutz, 1976); variation in the size of juveniles carried by precociously metamorphosing echinoderm larvae (Strathmann, 1971); variation in the age at which the barnacle cement gland becomes active and amounts of cement produced to anchor pediveliger in oysters (Cheung and Nigrelli, 1972;Cranfield, 1974); and differences in larval respiration rates and swimming activity (Crisp, 1974). In general, when features associated with habitat search diminish in importance, those enhancing metamorphic success or larval survival should increase.…”