A reader wrote to us about hookworms, or what are believed to hookworms, afflicting his dog. Having observed the worms, which the reader described as 1/4 to 1/2 of an inch long with rounded (or perhaps “hooked” is the better term) ends, he asked what hookworms look like. We’ll address this specific question, but we’ll also say a few remarks about hookworms in general, just in case some of our readers are not familiar with this common parasitic worm found in dogs (and other mammals, including humans, for that matter).