Millipedes (class Diplopoda) are generally dark, though they may be red, yellow or pink. Unlike centipedes, these mild mannered arthropods have short antennae and what appear to be two pairs of short legs per segment. Turning the specimen over reveals that what appears to be a single segment dorsally is actually a pair of segments, a condition known as diplosegmentation.
The term ‘millipede’ actually means “thousand leg” though the number of legs range from 22 to 750. Most are detritovores, consuming decaying organic matter. Defenses are both physical and chemical. Hatchlings emerge with three pairs of legs, adding legs and segments with each molt.
My biggest challenge in photographin both centipedes and millipedes is getting the entire head and trunk in focus.
Source: Field Guide to the Insects and Spiders of North America, Arthur V. Evans, 2008.