592 CLASS III. MYRIAPODA. 



Fam. Polyxenidae. Polyxenus Latreille, pursues and destroys the vine- 

 louse (Phylloxera) ; Central and S. Europe, England. P. lagurus L. 

 <Fig. 354). 



Sub-order 2. Chilognatha.* 



The chitinous covering of the body is hardened by calcareous salts. 

 The labrum is fused to the cephalic shield and glandulae odoriferae are 

 present. The mouth parts have the form described for the order, and 

 consist of a pair of mandibles and a pair of maxillae (gnathochilarium). 

 The males always possess one or two pairs of copulatory appendages 

 on the last segment or on the 7th or on the 7th and 8th (according to 

 Silvestri these appendages are not modified legs and may or may not 

 coexist with the ordinary appendages). The anus is on the last segment. 



Tribe 1. Oniscomorpha. The body is short, strongly convex dorsally 

 and capable of being rolled into a ball ; body segments 11-13 in number ; 

 foramina repugnatoria in a single, median dorsal row, beginning in the 

 4th segment. Pleura and laminae pedigerae free. Genital apertures at 

 the base of the legs of the 2nd pair. No penis ; the copulatory appendages 

 are on the penultimate segment, which also bears one pair of legs. 

 Segments 1, 2, 3, and 4f and the penultimate (and in the male the ante- 

 penultimate) have one pair of legs, the other segments, except the last, 

 have two pairs. 



Fam. 1. Gervaisidae. Antennae approximated at their bases and 

 placed on the front of the head, eyes in a row at the sides of the head, 

 11 tergites, the infrabasal (mentum) of the gnathochilarium undivided. 

 Gervaisia Waga, palaearctic region. 



Fam. 2. Glomeridae. Antennae and eyes as in the Gervaisidae, 12 

 tergites, infrabasal divided. Glomeris Latr., palaearctic and Indo- 

 inalayan (Fig. 355). 



Fam. 3. Sphaerotheridae. Antennae apart at the base, at the sides 

 of the head ; eyes in several rows ; 13 tergites ; infrabasal undivided. 

 Sphaerotherium Brandt, Asia, Africa, Australia. Zephronia Gray. 



The family Glo- 

 m eri d e s m i d a e 

 (Sumatra and C. 

 Amer. ) closely similar 

 to the above, but 

 with 19-20 segments 

 and without fora- 



FIG. 355. a Glomeris mari/inata (after C. L. Koch), 6 maxillae mma repugnatoria, 

 (gnathochilarium) of Julus terrestris. has been placed in a 



tribe Limacomorpha 

 distinct from the Oniscomorpha. 



Tribe 2. Helminthomorpha. Body usually elongated, more or less 

 cylindrical, reliable into a ball or spiral. Segments 19 to 108. Foramina 

 repugnatoria placed on the sides of the body. Pleura free or fused with 

 tergites. Laminae pedigerae free or fused with pleura. Copulatory 

 appendages on segments 7 and 8, or 6, 7 and 8 ; legs in these segments 

 present or absent. 



Fam. 1. Callipodidae. Eyes in several rows ; pleura united to tergites, 



* Latzel, Silvestri, op. cit. 



t Pocock, Zool. Ergeb. einer. Reise in Ost-Indien (M. Weber), p. 322. 



