Observations on Reproduction, Prematuration, and Fertilization in Sabellaria Vulgaris

Annelida: Polychaeta

“…In others, there is an initial activation of the egg, called prematuration, which may occur before or after spawning. Dehorne, 1913), S. vulgaris (Waterman, 1934), and Pomatoceros triqueter (Cragg, 1939). Cleavage follows the completion of meiosis.…”

“…B. Prematuration in Sabellaria vulgaris is immediately manifested in a visible polarity of the oocyte (Waterman, 1934(Waterman, , 1936Novikoff, 1939a). Allyn (1912) concluded that germinal vesicle breakdown in Chaetopterus is probably inhibited in the ovary and that release of the oocyte into seawater simply separates the oocytes from the inhibitor.…”

Sessile Marine Invertebrates of Beaufort, North Carolina: A Study of Settlement, Growth, and Seasonal Fluctuations among Pile‐Dwelling Organisms

“…Young individuals were frequently found upon experimental tiles situated below low water mark, but for some reason few of them grew to full size. Waterman (1934) studied the reproductive processes of Sabel-Zaria vulgaris at Woods Hole, Massachusetts, where the species is abundant and produces gametes throughout the summer months. Of its breeding period he remarks : "It is said that fertilization occurs normally during May and June, but a second and shorter time has been found during the early part of August."…”

Novel two‐step Ca2+ increase and its mechanisms and functions at fertilization in oocytes of the annelidan worm Pseudopotamilla occelata

“…This phenomenon, which looks like a remote control operation, might be related to the presence of the protoplasmic filaments that connect the oocyte surface with the vitelline envelope. Similar filaments are present in a wide perivitelline space in mature oocytes of Sabellaria (Waterman 1934; Novikoff 1939). Electron microscopic analyses in oocytes of annelids such as Chaetopterus , Tylorrhynchus , and Neanthes reveal that these filaments are microvilli traversing not only the perivitelline space but also the vitelline envelope and that the tip of microvillus fuses the acrosome‐reacted sperm situated on the outer layer of the vitelline envelope (Anderson & Eckberg 1983; Sato & Osanai 1983; Sato & Osanai 1986).…”

“…At the beginning of the last century, annelidan worms such as Nereis , Sabellaria , and Chaetopterus were used for pioneering studies of fertilization processes (e.g. Lillie 1902, 1 911; Waterman 1934). In Sabellaria , naturally spawned oocytes become arrested at the first metaphase of meiosis (metaphase I; MI); a wide perivitelline space (~12 µm) is already present before fertilization, as a result of cortical reaction after spawning (Waterman 1934; Novikoff 1939; Costello et al .…”