The Millipede (Animalia > Arthropoda > Myriapoda > Diplopoda) is a segmented animal, with 2 pairs of legs on each segment. They are closely related to the centipede, which has a single pair of legs per segment. There are approximately 7000 species of Millipede, one of the largest species is the African Giant Black Millipede, which can grow to 11 inches and is found in tropical to sub-tropical Western Africa.

The name derives from Latin, milli meaning thousand and ped meaning foot. This is a misnomer, as the average millipede has between 80 and 400 legs, with the largest still being short of 1000 at around 750.

The millipede is an excellent burrower, but has a rather low top speed, which means it has developed curling into a ball as its primary defensive tactic, thus protecting the legs. Some variants also emit a poisonous/acidic secretion, or Hydrogen Cyanide. These secretions can be squirted up to 25cm but the millipede does not have fangs. There is relatively little danger to humans, no deaths have ever been (directly) due to a millipede, but care should be taken when handling a millipede, as it could cause irritation, brown staining and pain, especially to the eyes.

The Millipede lays eggs in the spring and the populations build during the summer. Under the best circumstances, populations can grow quickly. For keeping them as pets one must ensure the case is at least twice the length and the same width as an individual (or the largest individual in the case if kept communally). There should also be 3-4 inches of peat or potting soil, kept moist. There is an excellent article at Millipede pets, with more information.

wertperch says IIRC they are one of the oldest animal groups still about. That makes me like 'em too. Although they are a bloody nuisance in gardens sometimes - I lost a lot of potato crop to the litle buggers, and was thankful for the centipedes, which et 'em. - Which just goes to show you can take the Brit out of Britain.... I've had a look into this, and it appears that Dr Heather Wilson (Yale) and Dr Lyall Anderson (National Museums of Scotland) published a paper in the Journal of Paleontology, on a fossilised Millipede which left the primordial soup 420 million years ago, 20 million years before the previous record holder: the Crane fly (Daddy long legs).

rootbeer277 says Might be interesting to note that lemurs rub millipede secretions over themselves, although sources are divided on whether this is just to clean them off for eating or as a form of insect repellent. Could be both. I did a quick google, and found the same. Come on scientists, forget quantum gravity, why do lemurs rub themselves with millipedes? Prioritise!

Thanks to the excellent article on Wikipedia, eMedicine, http://www.ext.vt.edu/departments/entomology/factsheets/milliped.html and http://www.petbugs.com/caresheets/A-gigas.html