In the May 6 "Explainer," Christopher Beam suggested that both human cells and yeast cells have walls. Only yeast cells do.

In the May 5 "Green Lantern," Nina Shen Rastogi erroneously stated that 40 million mattresses end up in the trash each year. The estimated figure is closer to 20 million to 30 million mattresses and boxsprings.

In the May 5 "Jurisprudence," Dahlia Lithwick incorrectly attributed an article in Politico by Josh Gerstein to Ben Smith.

In the May 4 "Fighting Words," Christopher Hitchens wrote that neither the United States nor Germany had entered World War II as of September 1940. The Soviet Union had entered the war but not against Germany, which did not declare war against the Soviet Union until June 1941.

In the April 30 "Explainer," least weasels were described as weighing no more than 8 or 9 pounds. That's way off—they rarely weigh more than 3 or 4 ounces. The error was introduced during the editing process.

In the April 28 "Green Lantern," Nina Shen Rastogi presented the pounds of manure a typical cow, hog, and chicken produce in a year. The amount of manure each animal produces over its lifetime would have been more appropriate; the numbers in the column have been corrected accordingly.

In the April 24 "Explainer," Christopher Beam incorrectly suggested that subterfuge could be invoked to prove "actual malice" in libel cases. While it might come up in court, it would not decide the case.

If you believe you have found an inaccuracy in a Slate story, please send an e-mail to corrections@slate.com, and we will investigate. General comments should be posted in "The Fray," our reader discussion forum..