Beside the road I saw a very large establishment, the greatest distributor of sea shells in the world—and this in Wisconsin, which hasn’t known a sea since pre-Cambrian times.
Seashells in Wisconsin was interesting to me as well, so I tried to google it. I found this interesting link from a man who disagreed with Mr. Steinbeck.
https://fossilsandotherlivingthings.blogspot.com/2015/10/my-apologies-john-steinbeck-but-i-care.html