518 



MYRIAPODA. 



Fio. 423. Embryo of Stronqylvsoma (after E. 

 Metschuikoff). 



their eggs in earth. The just-hatched young often pass through 

 a metamorphosis, having at first only three or seven pairs of 

 legs in addition to the antennse, and a few somites without limbs 

 (fig. 423). The young animals undergo numerous moults, and 



gradually increase in size; the 

 extremities sprout out on the 

 somites, which are already 

 present. New somites . are 

 constricted off from the termi- 

 nal one until the full number 

 is completed; the number of 

 ocelli and of the joints of the 

 antennae is increased, and the 

 resemblance to the sexual animal is gradually perfected. In other 

 cases (Scolopendra, Geophilidce) the embryo already possesses the 

 full number of appendages. 



Order 1. CHILOPODA.* 



Myriapoda of usually flattened form, with long many-jointed 

 antenna, and mouth parts adapted for predatory habits, with only one 

 pair of appendages to each segment. 



The body is long and usually flat- 

 tened. The chitinous exoskeleton 

 is hardened on the dorsal and ven- 

 tral surface of each somite, consti- 

 tuting the tergal and sternal plates, 

 while on the sides of the somites it 

 remains soft. In certain fornis 

 some of the terga develop to large 

 shields, which over-lap the smaller 

 terga of the intermediate somites 

 (fig. 424). The number of legs is 

 never greater than that of the sepa- 

 rate segments, a single pair only 

 being developed on each segment. 

 The antennas are long and many- 

 jointed, and are inserted beneath the 

 frontal margin. The eyes are simple 

 or aggregated ocelli, except in the genus Scutigera which has facetted 



* Newport, " Monograph of the Class Myriapoda, order Chilopoda," Linnaan 

 Transactions, XTX. 



FIG. 421. LitJiolius forficatus (after 0. 

 L. Koch). Sf, Poison claws. 



