CHAPTEE XXVI. 



MYRIOPODA. 



Systematic : — 



I. Chilopoda, with a dorso-ventrally compressed body, two pairs 

 of maxillae, and one pair of maxillipedes ; with one pair of limbs 

 on each body-segment ; genital aperture on the penultimate segment. 



Geophilus, Lithobius, Scolopendra, Scutigera. 



II. Symphyla, small delicate forms with only twelve segments, 

 to each of which is added an intermediate segment ; with twelve 

 pairs of limbs on the principal segments ; with one pair of maxillae, 

 without maxillipedes ; genital aperture on the fourth segment ; a 

 single pair of branching tracheae opening on the head ; at the 

 posterior end, two stylet-like processes (cerci). 



ScoJopend rella. 



III. Pauropoda, small delicate forms with twelve body-segments, 

 nine of which only carry limbs ; with one pair of maxillae ; without 

 maxillipedes ; characterised by the possession of three long flagellae 

 on the antennae ; paired genital apertures situated at the base of 

 the second pair of legs ; tracheae not known. 



Pauropus. 



IV. Diplopoda (Chilognatha),* with cylindrical body ; with 

 one pair of maxillae (gnathochilarium), without maxillipedes ; the 

 fifth and subsequent segments are double, each carrying two pairs 

 of limbs ; genital aperture between the second and third pairs of 

 limbs. 



Polyxenus, Glomeris, Polydesmus, Strongylosoma, Jzdus. 



Oviposition and the Constitution of the Egg. 



The eggs of the Diplopoda are usually laid in large numbers, 

 enclosed in an earthen nest formed by the female, by whom they 

 are watched for a long time, often until the young are hatched. 



* [POCOCK subdivides the Diplopoda into the Pselaphognatha, containing the 

 single family Polyxenidae, and the Chilognatha. For recent views on relation- 

 ship of the Chilopoda and the Diplopoda, see footnote at the end of this chapter. 

 —Ed.] 



