The Florida Caecum
These two pictures show the same shell, the Florida Caecum, Caecum floridanum Stimpson, 1851, a tiny gastropod not uncommon on the sandy beaches of SW Florida and that measures no more than 4 mm (a tad beyond 1/8 inch). The genus name Caecum means “blind” in Latin, and the word is also used for any structure that ends in a blind tube or pouch. The photo on top was taken under a standard microscope, and the one on the bottom with a scanning electron microscope (SEM), a sophisticated piece of equipment that allows for visualization of great detail at very large magnifications, but at the expense of color: SEMs use electron beams instead of light, and that procedure does not capture color, only surface features.
The Florida Caecum, Caecum floridanum Stimpson, 1851, bottom photo taken with a scanning electron microscope.Both images by José H. Leal.