Gill-filaments sentence example
- Portion of the axis of the left ctenidium which is fused with the base of the foot, the two dotted lines indicating the origins of the two rows of gill-filaments.
- Later changes consist in the growth of the shell-valves over the whole area of the mantle-flaps, and in the multiplication of the gill-filaments and their 'consolidation to form gill-plates.
- It is important to note that the gill-filaments are formed one by one posteriorly.