Word of the week: “lunula,” which is something shaped like a small crescent. It refers to the small, pale area at the base of fingernails and toenails. The word literally means “small moon” in Latin.

n The feathers of birds evolved from the scales of their reptilian ancestors. As an artifact of that genealogy, modern birds still have scales on the lower parts of their feet and legs. The number of feathers a bird has depends on its size and its habitat.

What is the correct term for a native of St. Louis, Missouri?

A) St. Louisan

B) Louie

C) St. Louite

D) St. Louiser

Friday’s answer: The official logo of the EPA is a two-leafed flower, with the sun and an ocean contained within the flower’s blossom.