. Bulletin of the British Museum (Natural History). Fig. 2 Early development of Ostrea edulis, redrawn from Horst (1882), with presumptive dorsal region (shell gland and later the hinge) at top and anterior to right: a, gastrula; b, early trochophore; c, middle trochophore; d, late trochophore; e, early veliger. (a = anus, aa = anterior adductor, ap = animal pole, app = apical pit, m = mouth, pmc = presumptive mantle cavity, pmo = presumptive mouth opening, pt = prototroch, s = shell, sg = shell gland, v = velum, vp = vegetal pole.) (Fig. 1 of Waller, 1981.) 11. Pediveliger: terminal
. Bulletin of the British Museum (Natural History). Fig. 2 Early development of Ostrea edulis, redrawn from Horst (1882), with presumptive dorsal region (shell gland and later the hinge) at top and anterior to right: a, gastrula; b, early trochophore; c, middle trochophore; d, late trochophore; e, early veliger. (a = anus, aa = anterior adductor, ap = animal pole, app = apical pit, m = mouth, pmc = presumptive mantle cavity, pmo = presumptive mouth opening, pt = prototroch, s = shell, sg = shell gland, v = velum, vp = vegetal pole.) (Fig. 1 of Waller, 1981.) 11. Pediveliger: terminal phase of Prod. II when larva briefly develops a foot for crawling and searching for a suitable substrate for cementation. 12. Metamorphosis: loss of velum, foot and change of shell growth direction, accompanying settlement of veliger, cementation and beginning of benthic mode of life. 13. Dissoconch: co-marginal shell growth after , together with internal shell thickening. DESCRIPTION OF MATERIAL Liostrea plasties (Trautschold 1860) Fig. 4; Plates 1, 2 See Kelly (1984) for synonymy, which includes Liostrea bononia (Sauvagc & Rigaux, 1871). Material. 56 juveniles with prodissoconchs well preserved, 51 RV and 5 LV; together with 6() pediveliger prodissoconchs, with no dissoconch growth, which arc all more or less crushed and distorted. Figured specimens LL41326-32, BM(NH). Description. More or less equivalve, strongly opisthogyrous, longer than high, demarcation between Prod. I and Prod. II. Fig. 3 Anatomy of a young, newly released, six-day-old veliger larva of Ostrea edulis, redrawn from Erdmann (1935). (a = anus, aa = anterior adductor, ao = apical organ, bg = primordial byssal gland, dg = digestive gland, es = esophagus, m = mouth, mew = mantle cavity wall, me = mouth embayment, ml = mouth lobe, ms = free mesenchymal cell, pn = protonephridium, s = stomach, ss = style sac, v = velum, vr = velar retractor.) (Fig. 2 of Waller, 1981.) not sharply defined, Pro
Size: 1663px × 1503px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbritishmuseumnaturalhistory, bookcentury1900, bookcoll
