1. Despite their name (which means "1,000 legs"), millipedes do not have 1000 legs. Millipedes are invertebrates that have a hard exoskeleton and many jointed legs. Millipedes live on land in moist microhabitats (under rocks, in rotting logs, in leaf debris, or occasionally in burrows).
Anatomy: Millipedes have a segmented body, short antennae, and many legs. Each body segment has two pairs of legs that stick out from the sides of the body (each segment is really 2 segments fused together). Most millipedes have from 25 to 100 segments (47 to 197 pairs of legs); most have about 30 to 40 segments (and 57 to 77 pairs of legs). The legs move in a wave-like motion.
The body is divided into two parts, the head and a segmented trunk. Millipedes breathe through spiracles, holes positioned along the body. Millipedes have poor to no vision. Millipedes range in size from a fraction of an inch to about 9 inches (23 cm) long.
Diet: Most millipedes are herbivores (plant-eaters) that eat dead and decaying plant material, but a few are also carnivores (meat-eaters). Millipedes also occasionally eat moist, living plants.
Enemies: Birds, badgers, and shrews eat millipedes. When they are in danger, millipedes curl up in a spiral, protecting their soft undersides. They can also spray a bad-smelling liquid (hydrocyanic acid) that repels many predators.
Reproduction: Millipedes hatch from eggs - hatchlings have only the first three pairs of legs. There is some maternal care of the eggs. Millipedes molt (shed their old exoskeleton) as they grow - with each molt they gain more segments and legs.
Classification: Kingdom Animalia (animals), Phylum Arthropoda (jointed legs and an exoskeleton), Superclass Myriapoda ("many-footed" with a 2-segmented body - millipedes, centipedes, etc.), Class Diplopoda (millipedes). About 7,500 species of millipedes have been described.

2. Despite their name (which means "100 legs"), centipedes do not all have 100 legs. Centipedes are fast-moving, carnivorous, venomous invertebrates. They have a hard exoskeleton and jointed legs. They live on land in moist microhabitats (under rocks and logs, in leaf debris, or occasionally in burrows). A common centipede is the house centipede, Scutigera forceps, which is about 2 inches (5 cm) long and has 15 pairs of legs. Some centipedes (like Geophilus electricus) glow in the dark.
Anatomy: Centipedes have a flattened, segmented body, long antennae, and many legs (each leg is slightly longer than the one in front of it). Centipedes have from 15 to about 177 segments (but most have about 15). Each body segment has a pair of legs that stick out from the sides. A member of the genus Geophilus has 177 pairs of legs. When a leg is cut off it will regenerate. The body is divided into two parts, the head and a segmented trunk. They breathe through spiracles, holes positioned along the body.
Diet: Centipedes are carnivores (meat-eaters) that use venom to kill their prey. The venom comes from glands that open near the first pair of modified legs (which act as poisonous fangs). Their bite can be painful to a human but not lethal. Centipedes eat insects, earthworms, spiders, slugs, and other small animals. The largest centipede, Scolopendra gigas (from Trinidad in the West Indies), also eats mice and some small lizards. Scolopendra gigas grows to be about 10 inches (25 cm) long and 1 inch wide.
Enemies: Birds, toads, and shrews eat centipedes, as do some people.
Reproduction: The average female centipede lays 60 sticky eggs (which are fertilized internally). She drops the eggs into a hole she digs in the soil. Some centipedes care for their eggs and the hatchlings.