Complex sentence: The shell is large and solid, sculptured with numerous spiral cords, prominently granose over the upper part of the spire whorls and again, encircling the callus-filled umbilicus, but those between are mostly smooth.
Split into simpler sentences: The shell is large and solid, sculptured with numerous spiral cords. These cords are prominently granose over the upper part of the spire whorls and again, encircling the callus-filled umbilicus, but those in between are mostly smooth.