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Guide to Myriopoda. 
Table-case have been distinguished by differences in colour. The tropical 
No. 27. forms (Sphaer other ium, Zephronia, etc.), occurring in South Africa, 
Madagascar and South East Asia, are often of large size. 
Order 2. Limacomorpha. 
In the Limacomorpha the body tapers anteriorly and posteriorly 
and the segments number from nineteen to twenty, the dorsal 
plate of the last of them being of small size. The copulatory feet 
are situated on the penultimate segment. The tracheae are 
branched, and there are no stink-glands. 
The small slug-like millipedes belonging to this sub-order occur 
in Java, Sumatra, and South America. As yet only three or four 
species are known ; they form a single family, Glomeridesmidae , 
with two genera, Glomeridesmus and Zephroniodesmus. 
Order 3. Helminthomorpha. 
The form of the body varies greatly in the Helminthomorpha, 
and the number of segments varies from nineteen to over a 
hundred in the different forms. The auxiliary copulatory organs 
of the male are situated on the seventh, on the seventh and eighth, 
or on the sixth, seventh and eighth segments. The tracheal tubes 
are not branched, but tufted. There are five sub-orders. 
Sub-order I.— LYSIOPETALOIDEA. 
The body of these millipedes is slender and sub-cylindrical, 
and the number of segments is large and variable. They have a wide 
distribution. 
Sub-order II.— COLOBOGNATHA. 
The Colobognatha differ from the other sub-orders of Helmin- 
thomorpha in that the mandibles and gnathochilarium are simplified, 
the mouth -parts being more or less of a suctorial type. The 
segments are numerous, and stink-glands are present. They are 
found in the tropical or warmer temperate countries of the globe. 
There are two families : Platydesmidae ( Platydesmus , etc.), and 
Siphonophoridae ( SiphonopJiora , Polyzonium, etc.). 
Sub-order III.— CHOEDEUMOIDEA. 
In the Chordeumoidea there'are always either thirty or thirty- 
two body-segments, bearing symmetrically placed bristles. Stink- 
glands are absent. The Chordeumoidea are chiefly European and 
North American forms. The sub-order is represented in this 
country by two species, the better known being Atractosoma 
polydes?noides. 
