338 



ZOOLOGY. 



three pairs of feet, and in this and other respects resembles 

 Podura. A second form, Eurypauropus, of Ryder, has six 

 segments, with nine pairs of feet wholly 

 concealed from above by the expanded seg- 

 ments. The antennae end in a terminal 

 globular hyaline body with a long pedicel, 

 as in Pauropus, and the mouth-parts are 

 as in that genus. E. spinosiis Ryder is 

 reddish brown, and one mm. in length. 



Order 3. Chilopoda. This group is rep- 

 resented by the centipede and Lithobius, 

 in which the body is flattened, the sternal 

 region being well developed. In Geophilus 

 (Fig. 303, G. bipuncticeps Wood) and allies 

 there are from thirty to two hundred seg- 

 ments. Our most common form is Litho- 

 bius Americanus Newport, found under 

 logs, etc. The centipede (Scolopendra 

 heros Girard) is very poisonous, the poison- 

 sac being lodged in the two large fangs or 

 {tried vSw! o 3 f 5 he e ad ni ' st pair of legs. In Cermatia the body is 

 pair o? l f eet* and first snoi 'tj with compound eyes and remarkably 

 long slender legs. C. forceps Rafinesque, of 

 the Middle and Southern States, is said to be poisonous; it 

 preys upon spiders. (Wood's Myriopoda of North America, 

 1865.) 



CLASS V. AKACHNIDA (Spiders, etc.). 



Characters of Arachnida. The bodies of spiders and scor- 

 pions, etc., are divided into two 

 regions, a head-thorax and abdomen, 

 the head being closely united witli 

 the thorax. There are no antennae, 

 only a pair of mandibles and a pair 

 of maxillae, with four pairs of legs. 

 There are never any compound eyes. 

 The young are usually like the adult, 

 except in the mites, in which there 

 is a slight metamorphosis. In all 

 Arachnida there is a liver, this organ not being present in 

 the winged insects. 



Fig. 305. Head of Pauropus 

 Luhbockii. Much enlarged. 



