MILLIPEDES AND 
CENTIPEDES 
{Myriapoda*) 
Millipedes and Centipedes breathe by means of air tubes 
(tracheae) like the Insects. They resemble each other by the 
elongated shape of the body which is divided into a large num- 
ber of ring-like pieces or segments. The head is distinct from 
the body and is regarded as formed by the fusion of four seg- 
ments. Most of the segments bear legs. The differences 
between the two groups are as follows : 
Millipedes {Diplopoda or CMlognatha) are cylindrical in 
shape ; the first four or five segments of the body have only one 
pair of legs each or are legless altogether, and the last segment 
is legless too, but all other segments have two pairs of legs 
each; antennae and legs are short; the jaws are small a^nd 
without poison glands. They live on vegetable matter and are 
harmless. Omitting a great number of small species we 
mention only three well-known forms. The large black or red- 
brown Millipedes which reach a length of 9 inches and above, 
belong to the genera SpirostrepUis and Thyropygus. Their body 
has more than thirty segments. The Pill-Millipedes which, 
when rolled up, resemble a ball, belong to the genus Zephronia, 
Their body has only thirteen segments. The largest, when 
rolled up, measure about I % inches in diameter. Easily dis- 
tinguished are also the various species of Acanthodesmus in 
which each segment bears at its sides a lobe-like process. They 
have twenty segments. 
Centipedes {ChHop&da) have a flattened body ; each seg- 
ment has one pair of legs only ; the antennae are iong ; so are 
the legs which enable these animals to move rapidly ; they have 
powerful jaws with poison glands and live on animal food. Of 
larger species the most common one here is Scolopendra sub- 
spinipes. A full-grown specimen in the collection measures 
6J4 inches. An exceedingly slender species, measuring a little 
