11. Growth lines outline a ventral hyponomic sinus but are otherwise transverse.12. Sculpture consists only of growth lines , sometimes with delicate spiral ornamentation. 13. Growth lines are usually biconvex, forming ventral and lateral sinuses.14. The shell is surface smooth, covered merely by growth lines which form two salients. 15. The external surface is smooth, ornamented only by growth lines . 16. The shell itself bears short radial ribs, sinuous growth lines , and prominent longitudinal striae. 17. The shell is coarsely ribbed and contains growth lines . 18. Growth lines are fine, forward slanting, concavo-convex; indicate well developed ventrolateral salients and hyponomic sinus.19. In the intervals of the longitudinals and parallel to them are very faint growth lines . 20. Let's see how the revenue growth line comes along,"
