338 



zooLoar. 



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



Podura. A second form, Eurypauropus, of Eyder, 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. spinosus Ryder is 

 reddish brown, and one mm. in length. 



Order 3. Chilopoda. — This group is rep- 

 resented by the centipede and Litholius, 

 in which the body is flattened, the sternal 

 region being well developed. In Geophilus 

 (Fig. 303, 0. hipuncticeps Wood) and allies 

 there are from thirty to two hundred seg- 

 ments. Our most common form is Litho- 

 bius Americanus liTewport, found under 

 logs, etc. The centipede {Scolopendra 

 heros Girard) is very poisonous, the poison- 

 sac being lodged in the two large fangs or 

 first pair of legs. In Cermatia the body is 

 short, with compound eyes and remarkably 

 long slender legs. G. forceps llafinesque, of 



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



preys upon spiders. 



Fig. SOi.— Pauropus 

 LvboocMl. Much en- 

 larged. Fig. 805 en- 

 larged view, of head 

 ana antenuse and iirst 

 pair of feet. 



Class III. — Arachistda {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 with 

 the thorax. There are no antennae, 

 only a pair of mandibles and a pair 

 of maxillae, with four paii's 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. 



. 305.— Head of Pauro, 

 Mucti enlarged. 



