Fig. 1. Adults and egg masses of Tritonia challengeriana (Antarctic; A,C,E) and T. diomedea (temperate; B,D,F). (A,B) Adults. (C,D) Egg masses (macro view). The egg mass of T. challengeriana (C) is in situ; the egg mass of T. diomedea was removed from its substrate with a razor blade. (E) Cut section of a egg mass of T. challengeriana with embryos spilling out of the cut end, showing gelatinous egg string in which embryos are contained. White spheroids are individual embryos at an early cleavage stage. (F) Uncut sections of coiled egg mass of T. diomedea, showing embryos (small yellow dots) in egg capsules (clusters of yellow embryos) contained within the mucous sleeve.