NURSE-EGG FEEDING PROSOBRANCHS - A COMPARATIVE BIOCHEMICAL AND ELECTROPHORETIC ANALYSIS OF EGGS AND HATCHLINGS

A biochemical study of the eggs and hatchlings of cold-temperate and a rctic-boreal (Buccinum undatum Linne, 1758, and B. cyaneum Bruguiere, 1792, respectively) and tropical (Fasciolaria tulipa hollisteri Weisbo rd, 1962, Fusinus closter Philippi, 1850, and Enaletes tulipa Chenu, 1 843) nurse-egg feeding gastropods was carried out to determine if the total protein, glycogen, and lipid contained in eggs and nurse eggs we re enough to account for the same totals in the hatchlings. An electro phoretic study was also conducted on the eggs and hatchlings of the fi ve species in order to compare qualitatively the patterns of egg prote ins and to determine how much of these were converted to other molecul ar weight proteins in the hatchling. Biochemical analysis indicated th at the buccinids and the vermetid had more-or-less enough material in eggs and nurse eggs to account for the total in the hatchling. However , fasciolariids did not have sufficient material in eggs and nurse egg s to account for the hatchlings, so some of the material must come fro m another source within the egg capsule. Different families exhibited different patterns of electrophoretic egg proteins and all species con verted most of the high molecular weight (HMW) egg proteins to differe nt low molecular weight (LMW) proteins with the exception of F. t. hol listeri, which retained most of the HMW proteins. This study indicates that there are taxonomic differences at the family level in the bioch emical construction of the hatchlings and in the electrophoretic patte rn of the eggs.